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| <a href="#404" id="404">404</a> |
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| <a href="#408" id="408">408</a> |
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| <a href="#417" id="417">417</a> |
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| <a href="#419" id="419">419</a> |
| <a href="#420" id="420">420</a> |
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| <a href="#422" id="422">422</a> |
| <a href="#423" id="423">423</a> |
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| <a href="#427" id="427">427</a> |
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| <a href="#440" id="440">440</a> |
| <a href="#441" id="441">441</a> |
| <a href="#442" id="442">442</a> |
| <a href="#443" id="443">443</a> |
| <a href="#444" id="444">444</a> |
| <a href="#445" id="445">445</a> |
| <a href="#446" id="446">446</a> |
| <a href="#447" id="447">447</a> |
| <a href="#448" id="448">448</a> |
| <a href="#449" id="449">449</a> |
| <a href="#450" id="450">450</a> |
| <a href="#451" id="451">451</a> |
| <a href="#452" id="452">452</a> |
| <a href="#453" id="453">453</a> |
| <a href="#454" id="454">454</a> |
| <a href="#455" id="455">455</a> |
| <a href="#456" id="456">456</a> |
| <a href="#457" id="457">457</a> |
| <a href="#458" id="458">458</a> |
| <a href="#459" id="459">459</a> |
| <a href="#460" id="460">460</a> |
| <a href="#461" id="461">461</a> |
| <a href="#462" id="462">462</a> |
| <a href="#463" id="463">463</a> |
| <a href="#464" id="464">464</a> |
| <a href="#465" id="465">465</a> |
| <a href="#466" id="466">466</a> |
| <a href="#467" id="467">467</a> |
| <a href="#468" id="468">468</a> |
| <a href="#469" id="469">469</a> |
| <a href="#470" id="470">470</a> |
| <a href="#471" id="471">471</a> |
| <a href="#472" id="472">472</a> |
| <a href="#473" id="473">473</a> |
| <a href="#474" id="474">474</a> |
| <a href="#475" id="475">475</a> |
| <a href="#476" id="476">476</a> |
| <a href="#477" id="477">477</a> |
| <a href="#478" id="478">478</a> |
| <a href="#479" id="479">479</a> |
| <a href="#480" id="480">480</a> |
| <a href="#481" id="481">481</a> |
| <a href="#482" id="482">482</a> |
| <a href="#483" id="483">483</a> |
| <a href="#484" id="484">484</a> |
| <a href="#485" id="485">485</a> |
| <a href="#486" id="486">486</a> |
| <a href="#487" id="487">487</a> |
| <a href="#488" id="488">488</a> |
| <a href="#489" id="489">489</a> |
| <a href="#490" id="490">490</a> |
| <a href="#491" id="491">491</a> |
| <a href="#492" id="492">492</a> |
| <a href="#493" id="493">493</a> |
| <a href="#494" id="494">494</a> |
| <a href="#495" id="495">495</a> |
| <a href="#496" id="496">496</a> |
| <a href="#497" id="497">497</a> |
| <a href="#498" id="498">498</a> |
| <a href="#499" id="499">499</a> |
| <a href="#500" id="500">500</a> |
| <a href="#501" id="501">501</a> |
| <a href="#502" id="502">502</a> |
| <a href="#503" id="503">503</a> |
| <a href="#504" id="504">504</a> |
| <a href="#505" id="505">505</a> |
| <a href="#506" id="506">506</a> |
| <a href="#507" id="507">507</a> |
| <a href="#508" id="508">508</a> |
| <a href="#509" id="509">509</a> |
| <a href="#510" id="510">510</a> |
| <a href="#511" id="511">511</a> |
| <a href="#512" id="512">512</a> |
| <a href="#513" id="513">513</a> |
| <a href="#514" id="514">514</a> |
| <a href="#515" id="515">515</a> |
| <a href="#516" id="516">516</a> |
| <a href="#517" id="517">517</a> |
| <a href="#518" id="518">518</a> |
| <a href="#519" id="519">519</a> |
| <a href="#520" id="520">520</a> |
| <a href="#521" id="521">521</a> |
| <a href="#522" id="522">522</a> |
| <a href="#523" id="523">523</a> |
| <a href="#524" id="524">524</a> |
| <a href="#525" id="525">525</a> |
| <a href="#526" id="526">526</a> |
| <a href="#527" id="527">527</a> |
| <a href="#528" id="528">528</a> |
| <a href="#529" id="529">529</a> |
| <a href="#530" id="530">530</a> |
| <a href="#531" id="531">531</a> |
| <a href="#532" id="532">532</a> |
| <a href="#533" id="533">533</a> |
| <a href="#534" id="534">534</a> |
| <a href="#535" id="535">535</a> |
| <a href="#536" id="536">536</a> |
| <a href="#537" id="537">537</a> |
| <a href="#538" id="538">538</a> |
| <a href="#539" id="539">539</a> |
| <a href="#540" id="540">540</a> |
| <a href="#541" id="541">541</a> |
| <a href="#542" id="542">542</a> |
| <a href="#543" id="543">543</a> |
| <a href="#544" id="544">544</a> |
| <a href="#545" id="545">545</a> |
| <a href="#546" id="546">546</a> |
| <a href="#547" id="547">547</a> |
| <a href="#548" id="548">548</a> |
| <a href="#549" id="549">549</a> |
| <a href="#550" id="550">550</a> |
| <a href="#551" id="551">551</a> |
| <a href="#552" id="552">552</a> |
| <a href="#553" id="553">553</a> |
| <a href="#554" id="554">554</a> |
| <a href="#555" id="555">555</a> |
| <a href="#556" id="556">556</a> |
| <a href="#557" id="557">557</a> |
| <a href="#558" id="558">558</a> |
| <a href="#559" id="559">559</a> |
| <a href="#560" id="560">560</a> |
| <a href="#561" id="561">561</a> |
| <a href="#562" id="562">562</a> |
| <a href="#563" id="563">563</a> |
| <a href="#564" id="564">564</a> |
| <a href="#565" id="565">565</a> |
| <a href="#566" id="566">566</a> |
| <a href="#567" id="567">567</a> |
| <a href="#568" id="568">568</a> |
| <a href="#569" id="569">569</a> |
| <a href="#570" id="570">570</a> |
| <a href="#571" id="571">571</a> |
| <a href="#572" id="572">572</a> |
| <a href="#573" id="573">573</a> |
| <a href="#574" id="574">574</a> |
| <a href="#575" id="575">575</a> |
| <a href="#576" id="576">576</a> |
| <a href="#577" id="577">577</a> |
| <a href="#578" id="578">578</a> |
| <a href="#579" id="579">579</a> |
| <a href="#580" id="580">580</a> |
| <a href="#581" id="581">581</a> |
| <a href="#582" id="582">582</a> |
| <a href="#583" id="583">583</a> |
| <a href="#584" id="584">584</a> |
| <a href="#585" id="585">585</a> |
| <a href="#586" id="586">586</a> |
| <a href="#587" id="587">587</a> |
| <a href="#588" id="588">588</a> |
| <a href="#589" id="589">589</a> |
| <a href="#590" id="590">590</a> |
| <a href="#591" id="591">591</a> |
| <a href="#592" id="592">592</a> |
| <a href="#593" id="593">593</a> |
| <a href="#594" id="594">594</a> |
| <a href="#595" id="595">595</a> |
| <a href="#596" id="596">596</a> |
| <a href="#597" id="597">597</a> |
| <a href="#598" id="598">598</a> |
| <a href="#599" id="599">599</a> |
| <a href="#600" id="600">600</a> |
| <a href="#601" id="601">601</a> |
| <a href="#602" id="602">602</a> |
| <a href="#603" id="603">603</a> |
| <a href="#604" id="604">604</a> |
| <a href="#605" id="605">605</a> |
| <a href="#606" id="606">606</a> |
| <a href="#607" id="607">607</a> |
| <a href="#608" id="608">608</a> |
| <a href="#609" id="609">609</a> |
| <a href="#610" id="610">610</a> |
| <a href="#611" id="611">611</a> |
| <a href="#612" id="612">612</a> |
| <a href="#613" id="613">613</a> |
| <a href="#614" id="614">614</a> |
| <a href="#615" id="615">615</a> |
| <a href="#616" id="616">616</a> |
| <a href="#617" id="617">617</a> |
| <a href="#618" id="618">618</a> |
| <a href="#619" id="619">619</a> |
| <a href="#620" id="620">620</a> |
| <a href="#621" id="621">621</a> |
| <a href="#622" id="622">622</a> |
| <a href="#623" id="623">623</a> |
| <a href="#624" id="624">624</a> |
| <a href="#625" id="625">625</a> |
| <a href="#626" id="626">626</a> |
| <a href="#627" id="627">627</a> |
| <a href="#628" id="628">628</a> |
| <a href="#629" id="629">629</a> |
| <a href="#630" id="630">630</a> |
| <a href="#631" id="631">631</a> |
| <a href="#632" id="632">632</a> |
| <a href="#633" id="633">633</a> |
| <a href="#634" id="634">634</a> |
| <a href="#635" id="635">635</a> |
| <a href="#636" id="636">636</a> |
| <a href="#637" id="637">637</a> |
| <a href="#638" id="638">638</a> |
| <a href="#639" id="639">639</a> |
| <a href="#640" id="640">640</a> |
| <a href="#641" id="641">641</a> |
| <a href="#642" id="642">642</a> |
| <a href="#643" id="643">643</a> |
| <a href="#644" id="644">644</a> |
| <a href="#645" id="645">645</a> |
| <a href="#646" id="646">646</a> |
| <a href="#647" id="647">647</a> |
| <a href="#648" id="648">648</a> |
| <a href="#649" id="649">649</a> |
| <a href="#650" id="650">650</a> |
| <a href="#651" id="651">651</a> |
| <a href="#652" id="652">652</a> |
| <a href="#653" id="653">653</a> |
| <a href="#654" id="654">654</a> |
| <a href="#655" id="655">655</a> |
| <a href="#656" id="656">656</a> |
| <a href="#657" id="657">657</a> |
| <a href="#658" id="658">658</a> |
| <a href="#659" id="659">659</a> |
| <a href="#660" id="660">660</a> |
| <a href="#661" id="661">661</a> |
| <a href="#662" id="662">662</a> |
| <a href="#663" id="663">663</a> |
| <a href="#664" id="664">664</a> |
| <a href="#665" id="665">665</a> |
| <a href="#666" id="666">666</a> |
| <a href="#667" id="667">667</a> |
| <a href="#668" id="668">668</a> |
| <a href="#669" id="669">669</a> |
| <a href="#670" id="670">670</a> |
| <a href="#671" id="671">671</a> |
| <a href="#672" id="672">672</a> |
| <a href="#673" id="673">673</a> |
| <a href="#674" id="674">674</a> |
| <a href="#675" id="675">675</a> |
| <a href="#676" id="676">676</a> |
| <a href="#677" id="677">677</a> |
| <a href="#678" id="678">678</a> |
| <a href="#679" id="679">679</a> |
| <a href="#680" id="680">680</a> |
| <a href="#681" id="681">681</a> |
| <a href="#682" id="682">682</a> |
| <a href="#683" id="683">683</a> |
| <a href="#684" id="684">684</a> |
| <a href="#685" id="685">685</a> |
| <a href="#686" id="686">686</a> |
| <a href="#687" id="687">687</a> |
| <a href="#688" id="688">688</a> |
| <a href="#689" id="689">689</a> |
| <a href="#690" id="690">690</a> |
| <a href="#691" id="691">691</a> |
| <a href="#692" id="692">692</a> |
| <a href="#693" id="693">693</a> |
| <a href="#694" id="694">694</a> |
| <a href="#695" id="695">695</a> |
| <a href="#696" id="696">696</a> |
| <a href="#697" id="697">697</a> |
| <a href="#698" id="698">698</a> |
| <a href="#699" id="699">699</a> |
| <a href="#700" id="700">700</a> |
| <a href="#701" id="701">701</a> |
| <a href="#702" id="702">702</a> |
| <a href="#703" id="703">703</a> |
| <a href="#704" id="704">704</a> |
| <a href="#705" id="705">705</a> |
| <a href="#706" id="706">706</a> |
| <a href="#707" id="707">707</a> |
| <a href="#708" id="708">708</a> |
| <a href="#709" id="709">709</a> |
| <a href="#710" id="710">710</a> |
| <a href="#711" id="711">711</a> |
| <a href="#712" id="712">712</a> |
| <a href="#713" id="713">713</a> |
| <a href="#714" id="714">714</a> |
| <a href="#715" id="715">715</a> |
| <a href="#716" id="716">716</a> |
| <a href="#717" id="717">717</a> |
| <a href="#718" id="718">718</a> |
| <a href="#719" id="719">719</a> |
| <a href="#720" id="720">720</a> |
| <a href="#721" id="721">721</a> |
| <a href="#722" id="722">722</a> |
| <a href="#723" id="723">723</a> |
| <a href="#724" id="724">724</a> |
| <a href="#725" id="725">725</a> |
| <a href="#726" id="726">726</a> |
| <a href="#727" id="727">727</a> |
| <a href="#728" id="728">728</a> |
| <a href="#729" id="729">729</a> |
| <a href="#730" id="730">730</a> |
| <a href="#731" id="731">731</a> |
| <a href="#732" id="732">732</a> |
| <a href="#733" id="733">733</a> |
| <a href="#734" id="734">734</a> |
| <a href="#735" id="735">735</a> |
| <a href="#736" id="736">736</a> |
| <a href="#737" id="737">737</a> |
| <a href="#738" id="738">738</a> |
| <a href="#739" id="739">739</a> |
| <a href="#740" id="740">740</a> |
| <a href="#741" id="741">741</a> |
| <a href="#742" id="742">742</a> |
| <a href="#743" id="743">743</a> |
| <a href="#744" id="744">744</a> |
| <a href="#745" id="745">745</a> |
| <a href="#746" id="746">746</a> |
| <a href="#747" id="747">747</a> |
| <a href="#748" id="748">748</a> |
| <a href="#749" id="749">749</a> |
| <a href="#750" id="750">750</a> |
| <a href="#751" id="751">751</a> |
| <a href="#752" id="752">752</a> |
| <a href="#753" id="753">753</a> |
| <a href="#754" id="754">754</a> |
| <a href="#755" id="755">755</a> |
| <a href="#756" id="756">756</a> |
| <a href="#757" id="757">757</a> |
| <a href="#758" id="758">758</a> |
| <a href="#759" id="759">759</a> |
| <a href="#760" id="760">760</a> |
| <a href="#761" id="761">761</a> |
| <a href="#762" id="762">762</a> |
| <a href="#763" id="763">763</a> |
| <a href="#764" id="764">764</a> |
| <a href="#765" id="765">765</a> |
| <a href="#766" id="766">766</a> |
| <a href="#767" id="767">767</a> |
| <a href="#768" id="768">768</a> |
| <a href="#769" id="769">769</a> |
| <a href="#770" id="770">770</a> |
| <a href="#771" id="771">771</a> |
| <a href="#772" id="772">772</a> |
| <a href="#773" id="773">773</a> |
| <a href="#774" id="774">774</a> |
| <a href="#775" id="775">775</a> |
| <a href="#776" id="776">776</a> |
| <a href="#777" id="777">777</a> |
| <a href="#778" id="778">778</a> |
| <a href="#779" id="779">779</a> |
| <a href="#780" id="780">780</a> |
| <a href="#781" id="781">781</a> |
| <a href="#782" id="782">782</a> |
| <a href="#783" id="783">783</a> |
| <a href="#784" id="784">784</a> |
| <a href="#785" id="785">785</a> |
| <a href="#786" id="786">786</a> |
| <a href="#787" id="787">787</a> |
| <a href="#788" id="788">788</a> |
| <a href="#789" id="789">789</a> |
| <a href="#790" id="790">790</a> |
| <a href="#791" id="791">791</a> |
| <a href="#792" id="792">792</a> |
| <a href="#793" id="793">793</a> |
| <a href="#794" id="794">794</a> |
| <a href="#795" id="795">795</a> |
| <a href="#796" id="796">796</a> |
| <a href="#797" id="797">797</a> |
| <a href="#798" id="798">798</a> |
| <a href="#799" id="799">799</a> |
| <a href="#800" id="800">800</a> |
| <a href="#801" id="801">801</a> |
| <a href="#802" id="802">802</a> |
| <a href="#803" id="803">803</a> |
| <a href="#804" id="804">804</a> |
| <a href="#805" id="805">805</a> |
| <a href="#806" id="806">806</a> |
| <a href="#807" id="807">807</a> |
| <a href="#808" id="808">808</a> |
| <a href="#809" id="809">809</a> |
| <a href="#810" id="810">810</a> |
| <a href="#811" id="811">811</a> |
| <a href="#812" id="812">812</a> |
| <a href="#813" id="813">813</a> |
| <a href="#814" id="814">814</a> |
| <a href="#815" id="815">815</a> |
| <a href="#816" id="816">816</a> |
| <a href="#817" id="817">817</a> |
| <a href="#818" id="818">818</a> |
| <a href="#819" id="819">819</a> |
| <a href="#820" id="820">820</a> |
| <a href="#821" id="821">821</a> |
| <a href="#822" id="822">822</a> |
| <a href="#823" id="823">823</a> |
| <a href="#824" id="824">824</a> |
| <a href="#825" id="825">825</a> |
| <a href="#826" id="826">826</a> |
| <a href="#827" id="827">827</a> |
| <a href="#828" id="828">828</a> |
| <a href="#829" id="829">829</a> |
| <a href="#830" id="830">830</a> |
| <a href="#831" id="831">831</a> |
| <a href="#832" id="832">832</a> |
| <a href="#833" id="833">833</a> |
| <a href="#834" id="834">834</a> |
| <a href="#835" id="835">835</a> |
| <a href="#836" id="836">836</a> |
| <a href="#837" id="837">837</a> |
| <a href="#838" id="838">838</a> |
| <a href="#839" id="839">839</a> |
| <a href="#840" id="840">840</a> |
| <a href="#841" id="841">841</a> |
| <a href="#842" id="842">842</a> |
| <a href="#843" id="843">843</a> |
| <a href="#844" id="844">844</a> |
| <a href="#845" id="845">845</a> |
| <a href="#846" id="846">846</a> |
| <a href="#847" id="847">847</a> |
| <a href="#848" id="848">848</a> |
| <a href="#849" id="849">849</a> |
| <a href="#850" id="850">850</a> |
| <a href="#851" id="851">851</a> |
| <a href="#852" id="852">852</a> |
| <a href="#853" id="853">853</a> |
| <a href="#854" id="854">854</a> |
| <a href="#855" id="855">855</a> |
| <a href="#856" id="856">856</a> |
| <a href="#857" id="857">857</a> |
| <a href="#858" id="858">858</a> |
| <a href="#859" id="859">859</a> |
| <a href="#860" id="860">860</a> |
| <a href="#861" id="861">861</a> |
| <a href="#862" id="862">862</a> |
| </pre></div><pre class="rust"><code><span class="comment">// Copyright (C) 2022, Cloudflare, Inc. |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright notice, |
| // this list of conditions and the following disclaimer. |
| // |
| // * Redistributions in binary form must reproduce the above copyright |
| // notice, this list of conditions and the following disclaimer in the |
| // documentation and/or other materials provided with the distribution. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS |
| // IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
| // THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| // PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR |
| // CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| // EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| // PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| // LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| // NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| </span><span class="doccomment">//! BBR Congestion Control |
| //! |
| //! This implementation is based on the following draft: |
| //! <https://tools.ietf.org/html/draft-cardwell-iccrg-bbr-congestion-control-00> |
| |
| </span><span class="kw">use </span><span class="kw">crate</span>::minmax::Minmax; |
| <span class="kw">use </span><span class="kw">crate</span>::recovery::<span class="kw-2">*</span>; |
| |
| <span class="kw">use </span>std::time::Duration; |
| |
| <span class="kw">pub static </span>BBR: CongestionControlOps = CongestionControlOps { |
| on_init, |
| reset, |
| on_packet_sent, |
| on_packets_acked, |
| congestion_event, |
| collapse_cwnd, |
| checkpoint, |
| rollback, |
| has_custom_pacing, |
| debug_fmt, |
| }; |
| |
| <span class="doccomment">/// A constant specifying the length of the BBR.BtlBw max filter window for |
| /// BBR.BtlBwFilter, BtlBwFilterLen is 10 packet-timed round trips. |
| </span><span class="kw">const </span>BTLBW_FILTER_LEN: Duration = Duration::from_secs(<span class="number">10</span>); |
| |
| <span class="doccomment">/// A constant specifying the minimum time interval between ProbeRTT states: 10 |
| /// secs. |
| </span><span class="kw">const </span>PROBE_RTT_INTERVAL: Duration = Duration::from_secs(<span class="number">10</span>); |
| |
| <span class="doccomment">/// A constant specifying the length of the RTProp min filter window. |
| </span><span class="kw">const </span>RTPROP_FILTER_LEN: Duration = PROBE_RTT_INTERVAL; |
| |
| <span class="doccomment">/// A constant specifying the minimum gain value that will allow the sending |
| /// rate to double each round (2/ln(2) ~= 2.89), used in Startup mode for both |
| /// BBR.pacing_gain and BBR.cwnd_gain. |
| </span><span class="kw">const </span>BBR_HIGH_GAIN: f64 = <span class="number">2.89</span>; |
| |
| <span class="doccomment">/// The minimal cwnd value BBR tries to target using: 4 packets, or 4 * SMSS |
| </span><span class="kw">const </span>BBR_MIN_PIPE_CWND_PKTS: usize = <span class="number">4</span>; |
| |
| <span class="doccomment">/// The number of phases in the BBR ProbeBW gain cycle: 8. |
| </span><span class="kw">const </span>BBR_GAIN_CYCLE_LEN: usize = <span class="number">8</span>; |
| |
| <span class="doccomment">/// A constant specifying the minimum duration for which ProbeRTT state holds |
| /// inflight to BBRMinPipeCwnd or fewer packets: 200 ms. |
| </span><span class="kw">const </span>PROBE_RTT_DURATION: Duration = Duration::from_millis(<span class="number">200</span>); |
| |
| <span class="doccomment">/// Pacing Gain Cycle. |
| </span><span class="kw">const </span>PACING_GAIN_CYCLE: [f64; BBR_GAIN_CYCLE_LEN] = |
| [<span class="number">5.0 </span>/ <span class="number">4.0</span>, <span class="number">3.0 </span>/ <span class="number">4.0</span>, <span class="number">1.0</span>, <span class="number">1.0</span>, <span class="number">1.0</span>, <span class="number">1.0</span>, <span class="number">1.0</span>, <span class="number">1.0</span>]; |
| |
| <span class="doccomment">/// A constant to check BBR.BtlBW is still growing. |
| </span><span class="kw">const </span>BTLBW_GROWTH_TARGET: f64 = <span class="number">1.25</span>; |
| |
| <span class="doccomment">/// BBR Internal State Machine. |
| </span><span class="attr">#[derive(Debug, PartialEq, Eq)] |
| </span><span class="kw">enum </span>BBRStateMachine { |
| Startup, |
| Drain, |
| ProbeBW, |
| ProbeRTT, |
| } |
| |
| <span class="doccomment">/// BBR Specific State Variables. |
| </span><span class="kw">pub struct </span>State { |
| <span class="comment">// The current state of a BBR flow in the BBR state machine. |
| </span>state: BBRStateMachine, |
| |
| <span class="comment">// The current pacing rate for a BBR flow, which controls inter-packet |
| // spacing. |
| </span>pacing_rate: u64, |
| |
| <span class="comment">// BBR's estimated bottleneck bandwidth available to the transport flow, |
| // estimated from the maximum delivery rate sample in a sliding window. |
| </span>btlbw: u64, |
| |
| <span class="comment">// The max filter used to estimate BBR.BtlBw. |
| </span>btlbwfilter: Minmax<u64>, |
| |
| <span class="comment">// BBR's estimated two-way round-trip propagation delay of the path, |
| // estimated from the windowed minimum recent round-trip delay sample. |
| </span>rtprop: Duration, |
| |
| <span class="comment">// The wall clock time at which the current BBR.RTProp sample was obtained. |
| </span>rtprop_stamp: Instant, |
| |
| <span class="comment">// A boolean recording whether the BBR.RTprop has expired and is due for a |
| // refresh with an application idle period or a transition into ProbeRTT |
| // state. |
| </span>rtprop_expired: bool, |
| |
| <span class="comment">// The dynamic gain factor used to scale BBR.BtlBw to produce |
| // BBR.pacing_rate. |
| </span>pacing_gain: f64, |
| |
| <span class="comment">// The dynamic gain factor used to scale the estimated BDP to produce a |
| // congestion window (cwnd). |
| </span>cwnd_gain: f64, |
| |
| <span class="comment">// A boolean that records whether BBR estimates that it has ever fully |
| // utilized its available bandwidth ("filled the pipe"). |
| </span>filled_pipe: bool, |
| |
| <span class="comment">// Count of packet-timed round trips elapsed so far. |
| </span>round_count: u64, |
| |
| <span class="comment">// A boolean that BBR sets to true once per packet-timed round trip, |
| // on ACKs that advance BBR.round_count. |
| </span>round_start: bool, |
| |
| <span class="comment">// packet.delivered value denoting the end of a packet-timed round trip. |
| </span>next_round_delivered: usize, |
| |
| <span class="comment">// Timestamp when ProbeRTT state ends. |
| </span>probe_rtt_done_stamp: <span class="prelude-ty">Option</span><Instant>, |
| |
| <span class="comment">// Checking if a roundtrip in ProbeRTT state ends. |
| </span>probe_rtt_round_done: bool, |
| |
| <span class="comment">// Checking if in the packet conservation mode during recovery. |
| </span>packet_conservation: bool, |
| |
| <span class="comment">// Saved cwnd before loss recovery. |
| </span>prior_cwnd: usize, |
| |
| <span class="comment">// Checking if restarting from idle. |
| </span>idle_restart: bool, |
| |
| <span class="comment">// Baseline level delivery rate for full pipe estimator. |
| </span>full_bw: u64, |
| |
| <span class="comment">// The number of round for full pipe estimator without much growth. |
| </span>full_bw_count: usize, |
| |
| <span class="comment">// Last time cycle_index is updated. |
| </span>cycle_stamp: Instant, |
| |
| <span class="comment">// Current index of pacing_gain_cycle[]. |
| </span>cycle_index: usize, |
| |
| <span class="comment">// The upper bound on the volume of data BBR allows in flight. |
| </span>target_cwnd: usize, |
| |
| <span class="comment">// Whether in the recovery episode. |
| </span>in_recovery: bool, |
| |
| <span class="comment">// Start time of the connection. |
| </span>start_time: Instant, |
| |
| <span class="comment">// Newly marked lost data size in bytes. |
| </span>newly_lost_bytes: usize, |
| |
| <span class="comment">// Newly acked data size in bytes. |
| </span>newly_acked_bytes: usize, |
| |
| <span class="comment">// bytes_in_flight before processing this ACK. |
| </span>prior_bytes_in_flight: usize, |
| } |
| |
| <span class="kw">impl </span>State { |
| <span class="kw">pub fn </span>new() -> <span class="self">Self </span>{ |
| <span class="kw">let </span>now = Instant::now(); |
| |
| State { |
| state: BBRStateMachine::Startup, |
| |
| pacing_rate: <span class="number">0</span>, |
| |
| btlbw: <span class="number">0</span>, |
| |
| btlbwfilter: Minmax::new(<span class="number">0</span>), |
| |
| rtprop: Duration::ZERO, |
| |
| rtprop_stamp: now, |
| |
| rtprop_expired: <span class="bool-val">false</span>, |
| |
| pacing_gain: <span class="number">0.0</span>, |
| |
| cwnd_gain: <span class="number">0.0</span>, |
| |
| filled_pipe: <span class="bool-val">false</span>, |
| |
| round_count: <span class="number">0</span>, |
| |
| round_start: <span class="bool-val">false</span>, |
| |
| next_round_delivered: <span class="number">0</span>, |
| |
| probe_rtt_done_stamp: <span class="prelude-val">None</span>, |
| |
| probe_rtt_round_done: <span class="bool-val">false</span>, |
| |
| packet_conservation: <span class="bool-val">false</span>, |
| |
| prior_cwnd: <span class="number">0</span>, |
| |
| idle_restart: <span class="bool-val">false</span>, |
| |
| full_bw: <span class="number">0</span>, |
| |
| full_bw_count: <span class="number">0</span>, |
| |
| cycle_stamp: now, |
| |
| cycle_index: <span class="number">0</span>, |
| |
| target_cwnd: <span class="number">0</span>, |
| |
| in_recovery: <span class="bool-val">false</span>, |
| |
| start_time: now, |
| |
| newly_lost_bytes: <span class="number">0</span>, |
| |
| newly_acked_bytes: <span class="number">0</span>, |
| |
| prior_bytes_in_flight: <span class="number">0</span>, |
| } |
| } |
| } |
| |
| <span class="comment">// When entering the recovery episode. |
| </span><span class="kw">fn </span>bbr_enter_recovery(r: <span class="kw-2">&mut </span>Recovery, in_flight: usize, now: Instant) { |
| r.bbr_state.prior_cwnd = per_ack::bbr_save_cwnd(r); |
| |
| r.congestion_window = in_flight.max(r.max_datagram_size); |
| r.congestion_recovery_start_time = <span class="prelude-val">Some</span>(now); |
| |
| r.bbr_state.packet_conservation = <span class="bool-val">true</span>; |
| r.bbr_state.in_recovery = <span class="bool-val">true</span>; |
| |
| r.bbr_state.newly_lost_bytes = <span class="number">0</span>; |
| |
| <span class="comment">// Start round now. |
| </span>r.bbr_state.next_round_delivered = r.delivery_rate.delivered(); |
| } |
| |
| <span class="comment">// When exiting the recovery episode. |
| </span><span class="kw">fn </span>bbr_exit_recovery(r: <span class="kw-2">&mut </span>Recovery) { |
| r.congestion_recovery_start_time = <span class="prelude-val">None</span>; |
| |
| r.bbr_state.packet_conservation = <span class="bool-val">false</span>; |
| r.bbr_state.in_recovery = <span class="bool-val">false</span>; |
| |
| per_ack::bbr_restore_cwnd(r); |
| } |
| |
| <span class="comment">// Congestion Control Hooks. |
| // |
| </span><span class="kw">fn </span>on_init(r: <span class="kw-2">&mut </span>Recovery) { |
| init::bbr_init(r); |
| } |
| |
| <span class="kw">fn </span>reset(r: <span class="kw-2">&mut </span>Recovery) { |
| r.bbr_state = State::new(); |
| |
| init::bbr_init(r); |
| } |
| |
| <span class="kw">fn </span>on_packet_sent(r: <span class="kw-2">&mut </span>Recovery, _sent_bytes: usize, _now: Instant) { |
| per_transmit::bbr_on_transmit(r); |
| } |
| |
| <span class="kw">fn </span>on_packets_acked(r: <span class="kw-2">&mut </span>Recovery, packets: <span class="kw-2">&mut </span>Vec<Acked>, now: Instant) { |
| r.bbr_state.prior_bytes_in_flight = r.bytes_in_flight; |
| |
| r.bbr_state.newly_acked_bytes = |
| packets.drain(..).fold(<span class="number">0</span>, |acked_bytes, p| { |
| r.bbr_state.prior_bytes_in_flight -= p.size; |
| |
| per_ack::bbr_update_model_and_state(r, <span class="kw-2">&</span>p, now); |
| |
| acked_bytes + p.size |
| }); |
| |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(pkt) = packets.last() { |
| <span class="kw">if </span>!r.in_congestion_recovery(pkt.time_sent) && r.bbr_state.in_recovery { |
| <span class="comment">// Upon exiting loss recovery. |
| </span>bbr_exit_recovery(r); |
| } |
| } |
| |
| per_ack::bbr_update_control_parameters(r, now); |
| |
| r.bbr_state.newly_lost_bytes = <span class="number">0</span>; |
| } |
| |
| <span class="kw">fn </span>congestion_event( |
| r: <span class="kw-2">&mut </span>Recovery, lost_bytes: usize, largest_lost_pkt: <span class="kw-2">&</span>Sent, now: Instant, |
| ) { |
| r.bbr_state.newly_lost_bytes = lost_bytes; |
| |
| <span class="comment">// Upon entering Fast Recovery. |
| </span><span class="kw">if </span>!r.in_congestion_recovery(largest_lost_pkt.time_sent) { |
| <span class="comment">// Upon entering Fast Recovery. |
| </span>bbr_enter_recovery(r, r.bytes_in_flight - lost_bytes, now); |
| } |
| } |
| |
| <span class="kw">fn </span>collapse_cwnd(r: <span class="kw-2">&mut </span>Recovery) { |
| r.bbr_state.prior_cwnd = per_ack::bbr_save_cwnd(r); |
| |
| reno::collapse_cwnd(r); |
| } |
| |
| <span class="kw">fn </span>checkpoint(_r: <span class="kw-2">&mut </span>Recovery) {} |
| |
| <span class="kw">fn </span>rollback(_r: <span class="kw-2">&mut </span>Recovery) -> bool { |
| <span class="bool-val">false |
| </span>} |
| |
| <span class="kw">fn </span>has_custom_pacing() -> bool { |
| <span class="bool-val">true |
| </span>} |
| |
| <span class="kw">fn </span>debug_fmt(r: <span class="kw-2">&</span>Recovery, f: <span class="kw-2">&mut </span>std::fmt::Formatter) -> std::fmt::Result { |
| <span class="kw">let </span>bbr = <span class="kw-2">&</span>r.bbr_state; |
| |
| <span class="macro">write!</span>( |
| f, |
| <span class="string">"bbr={{ state={:?} btlbw={} rtprop={:?} pacing_rate={} pacing_gain={} cwnd_gain={} target_cwnd={} send_quantum={} filled_pipe={} round_count={} }}"</span>, |
| bbr.state, bbr.btlbw, bbr.rtprop, bbr.pacing_rate, bbr.pacing_gain, bbr.cwnd_gain, bbr.target_cwnd, r.send_quantum(), bbr.filled_pipe, bbr.round_count |
| ) |
| } |
| |
| <span class="attr">#[cfg(test)] |
| </span><span class="kw">mod </span>tests { |
| <span class="kw">use super</span>::<span class="kw-2">*</span>; |
| |
| <span class="kw">use </span><span class="kw">crate</span>::recovery; |
| |
| <span class="kw">use </span>smallvec::smallvec; |
| |
| <span class="attr">#[test] |
| </span><span class="kw">fn </span>bbr_init() { |
| <span class="kw">let </span><span class="kw-2">mut </span>cfg = <span class="kw">crate</span>::Config::new(<span class="kw">crate</span>::PROTOCOL_VERSION).unwrap(); |
| cfg.set_cc_algorithm(recovery::CongestionControlAlgorithm::BBR); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>r = Recovery::new(<span class="kw-2">&</span>cfg); |
| |
| <span class="comment">// on_init() is called in Connection::new(), so it need to be |
| // called manually here. |
| </span>r.on_init(); |
| |
| <span class="macro">assert_eq!</span>( |
| r.cwnd(), |
| r.max_datagram_size * cfg.initial_congestion_window_packets |
| ); |
| <span class="macro">assert_eq!</span>(r.bytes_in_flight, <span class="number">0</span>); |
| |
| <span class="macro">assert_eq!</span>(r.bbr_state.state, BBRStateMachine::Startup); |
| } |
| |
| <span class="attr">#[test] |
| </span><span class="kw">fn </span>bbr_send() { |
| <span class="kw">let </span><span class="kw-2">mut </span>cfg = <span class="kw">crate</span>::Config::new(<span class="kw">crate</span>::PROTOCOL_VERSION).unwrap(); |
| cfg.set_cc_algorithm(recovery::CongestionControlAlgorithm::BBR); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>r = Recovery::new(<span class="kw-2">&</span>cfg); |
| <span class="kw">let </span>now = Instant::now(); |
| |
| r.on_init(); |
| r.on_packet_sent_cc(<span class="number">0</span>, <span class="number">1000</span>, now); |
| |
| <span class="macro">assert_eq!</span>(r.bytes_in_flight, <span class="number">1000</span>); |
| } |
| |
| <span class="attr">#[test] |
| </span><span class="kw">fn </span>bbr_startup() { |
| <span class="kw">let </span><span class="kw-2">mut </span>cfg = <span class="kw">crate</span>::Config::new(<span class="kw">crate</span>::PROTOCOL_VERSION).unwrap(); |
| cfg.set_cc_algorithm(recovery::CongestionControlAlgorithm::BBR); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>r = Recovery::new(<span class="kw-2">&</span>cfg); |
| <span class="kw">let </span>now = Instant::now(); |
| <span class="kw">let </span>mss = r.max_datagram_size; |
| |
| r.on_init(); |
| |
| <span class="comment">// Send 5 packets. |
| </span><span class="kw">for </span>pn <span class="kw">in </span><span class="number">0</span>..<span class="number">5 </span>{ |
| <span class="kw">let </span>pkt = Sent { |
| pkt_num: pn, |
| frames: <span class="macro">smallvec!</span>[], |
| time_sent: now, |
| time_acked: <span class="prelude-val">None</span>, |
| time_lost: <span class="prelude-val">None</span>, |
| size: mss, |
| ack_eliciting: <span class="bool-val">true</span>, |
| in_flight: <span class="bool-val">true</span>, |
| delivered: <span class="number">0</span>, |
| delivered_time: now, |
| first_sent_time: now, |
| is_app_limited: <span class="bool-val">false</span>, |
| tx_in_flight: <span class="number">0</span>, |
| lost: <span class="number">0</span>, |
| has_data: <span class="bool-val">false</span>, |
| pmtud: <span class="bool-val">false</span>, |
| }; |
| |
| r.on_packet_sent( |
| pkt, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| ); |
| } |
| |
| <span class="kw">let </span>rtt = Duration::from_millis(<span class="number">50</span>); |
| <span class="kw">let </span>now = now + rtt; |
| <span class="kw">let </span>cwnd_prev = r.cwnd(); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>acked = ranges::RangeSet::default(); |
| acked.insert(<span class="number">0</span>..<span class="number">5</span>); |
| |
| <span class="macro">assert_eq!</span>( |
| r.on_ack_received( |
| <span class="kw-2">&</span>acked, |
| <span class="number">25</span>, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| <span class="kw-2">&mut </span>Vec::new(), |
| ), |
| <span class="prelude-val">Ok</span>((<span class="number">0</span>, <span class="number">0</span>)), |
| ); |
| |
| <span class="macro">assert_eq!</span>(r.bbr_state.state, BBRStateMachine::Startup); |
| <span class="macro">assert_eq!</span>(r.cwnd(), cwnd_prev + mss * <span class="number">5</span>); |
| <span class="macro">assert_eq!</span>(r.bytes_in_flight, <span class="number">0</span>); |
| <span class="macro">assert_eq!</span>( |
| r.delivery_rate(), |
| ((mss * <span class="number">5</span>) <span class="kw">as </span>f64 / rtt.as_secs_f64()) <span class="kw">as </span>u64 |
| ); |
| <span class="macro">assert_eq!</span>(r.bbr_state.btlbw, r.delivery_rate()); |
| } |
| |
| <span class="attr">#[test] |
| </span><span class="kw">fn </span>bbr_congestion_event() { |
| <span class="kw">let </span><span class="kw-2">mut </span>cfg = <span class="kw">crate</span>::Config::new(<span class="kw">crate</span>::PROTOCOL_VERSION).unwrap(); |
| cfg.set_cc_algorithm(recovery::CongestionControlAlgorithm::BBR); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>r = Recovery::new(<span class="kw-2">&</span>cfg); |
| <span class="kw">let </span>now = Instant::now(); |
| <span class="kw">let </span>mss = r.max_datagram_size; |
| |
| r.on_init(); |
| |
| <span class="comment">// Send 5 packets. |
| </span><span class="kw">for </span>pn <span class="kw">in </span><span class="number">0</span>..<span class="number">5 </span>{ |
| <span class="kw">let </span>pkt = Sent { |
| pkt_num: pn, |
| frames: <span class="macro">smallvec!</span>[], |
| time_sent: now, |
| time_acked: <span class="prelude-val">None</span>, |
| time_lost: <span class="prelude-val">None</span>, |
| size: mss, |
| ack_eliciting: <span class="bool-val">true</span>, |
| in_flight: <span class="bool-val">true</span>, |
| delivered: <span class="number">0</span>, |
| delivered_time: now, |
| first_sent_time: now, |
| is_app_limited: <span class="bool-val">false</span>, |
| tx_in_flight: <span class="number">0</span>, |
| lost: <span class="number">0</span>, |
| has_data: <span class="bool-val">false</span>, |
| pmtud: <span class="bool-val">false</span>, |
| }; |
| |
| r.on_packet_sent( |
| pkt, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| ); |
| } |
| |
| <span class="kw">let </span>rtt = Duration::from_millis(<span class="number">50</span>); |
| <span class="kw">let </span>now = now + rtt; |
| |
| <span class="comment">// Make a packet loss to trigger a congestion event. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>acked = ranges::RangeSet::default(); |
| acked.insert(<span class="number">4</span>..<span class="number">5</span>); |
| |
| <span class="comment">// 2 acked, 2 x MSS lost. |
| </span><span class="macro">assert_eq!</span>( |
| r.on_ack_received( |
| <span class="kw-2">&</span>acked, |
| <span class="number">25</span>, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| <span class="kw-2">&mut </span>Vec::new(), |
| ), |
| <span class="prelude-val">Ok</span>((<span class="number">2</span>, <span class="number">2400</span>)), |
| ); |
| |
| <span class="comment">// Sent: 0, 1, 2, 3, 4, Acked 4. |
| </span><span class="macro">assert_eq!</span>(r.cwnd(), mss * <span class="number">4</span>); |
| <span class="comment">// Stil in flight: 2, 3. |
| </span><span class="macro">assert_eq!</span>(r.bytes_in_flight, mss * <span class="number">2</span>); |
| } |
| |
| <span class="attr">#[test] |
| </span><span class="kw">fn </span>bbr_drain() { |
| <span class="kw">let </span><span class="kw-2">mut </span>cfg = <span class="kw">crate</span>::Config::new(<span class="kw">crate</span>::PROTOCOL_VERSION).unwrap(); |
| cfg.set_cc_algorithm(recovery::CongestionControlAlgorithm::BBR); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>r = Recovery::new(<span class="kw-2">&</span>cfg); |
| <span class="kw">let </span>now = Instant::now(); |
| <span class="kw">let </span>mss = r.max_datagram_size; |
| |
| r.on_init(); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>pn = <span class="number">0</span>; |
| |
| <span class="comment">// Stop right before filled_pipe=true. |
| </span><span class="kw">for _ in </span><span class="number">0</span>..<span class="number">3 </span>{ |
| <span class="kw">let </span>pkt = Sent { |
| pkt_num: pn, |
| frames: <span class="macro">smallvec!</span>[], |
| time_sent: now, |
| time_acked: <span class="prelude-val">None</span>, |
| time_lost: <span class="prelude-val">None</span>, |
| size: mss, |
| ack_eliciting: <span class="bool-val">true</span>, |
| in_flight: <span class="bool-val">true</span>, |
| delivered: r.delivery_rate.delivered(), |
| delivered_time: now, |
| first_sent_time: now, |
| is_app_limited: <span class="bool-val">false</span>, |
| tx_in_flight: <span class="number">0</span>, |
| lost: <span class="number">0</span>, |
| has_data: <span class="bool-val">false</span>, |
| pmtud: <span class="bool-val">false</span>, |
| }; |
| |
| r.on_packet_sent( |
| pkt, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| ); |
| |
| pn += <span class="number">1</span>; |
| |
| <span class="kw">let </span>rtt = Duration::from_millis(<span class="number">50</span>); |
| |
| <span class="kw">let </span>now = now + rtt; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>acked = ranges::RangeSet::default(); |
| acked.insert(<span class="number">0</span>..pn); |
| |
| <span class="macro">assert_eq!</span>( |
| r.on_ack_received( |
| <span class="kw-2">&</span>acked, |
| <span class="number">25</span>, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| <span class="kw-2">&mut </span>Vec::new(), |
| ), |
| <span class="prelude-val">Ok</span>((<span class="number">0</span>, <span class="number">0</span>)), |
| ); |
| } |
| |
| <span class="comment">// Stop at right before filled_pipe=true. |
| </span><span class="kw">for _ in </span><span class="number">0</span>..<span class="number">5 </span>{ |
| <span class="kw">let </span>pkt = Sent { |
| pkt_num: pn, |
| frames: <span class="macro">smallvec!</span>[], |
| time_sent: now, |
| time_acked: <span class="prelude-val">None</span>, |
| time_lost: <span class="prelude-val">None</span>, |
| size: mss, |
| ack_eliciting: <span class="bool-val">true</span>, |
| in_flight: <span class="bool-val">true</span>, |
| delivered: r.delivery_rate.delivered(), |
| delivered_time: now, |
| first_sent_time: now, |
| is_app_limited: <span class="bool-val">false</span>, |
| tx_in_flight: <span class="number">0</span>, |
| lost: <span class="number">0</span>, |
| has_data: <span class="bool-val">false</span>, |
| pmtud: <span class="bool-val">false</span>, |
| }; |
| |
| r.on_packet_sent( |
| pkt, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| ); |
| |
| pn += <span class="number">1</span>; |
| } |
| |
| <span class="kw">let </span>rtt = Duration::from_millis(<span class="number">50</span>); |
| <span class="kw">let </span>now = now + rtt; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>acked = ranges::RangeSet::default(); |
| |
| <span class="comment">// We sent 5 packets, but ack only one, to stay |
| // in Drain state. |
| </span>acked.insert(<span class="number">0</span>..pn - <span class="number">4</span>); |
| |
| <span class="macro">assert_eq!</span>( |
| r.on_ack_received( |
| <span class="kw-2">&</span>acked, |
| <span class="number">25</span>, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| <span class="kw-2">&mut </span>Vec::new(), |
| ), |
| <span class="prelude-val">Ok</span>((<span class="number">0</span>, <span class="number">0</span>)), |
| ); |
| |
| <span class="comment">// Now we are in Drain state. |
| </span><span class="macro">assert!</span>(r.bbr_state.filled_pipe); |
| <span class="macro">assert_eq!</span>(r.bbr_state.state, BBRStateMachine::Drain); |
| <span class="macro">assert!</span>(r.bbr_state.pacing_gain < <span class="number">1.0</span>); |
| } |
| |
| <span class="attr">#[test] |
| </span><span class="kw">fn </span>bbr_probe_bw() { |
| <span class="kw">let </span><span class="kw-2">mut </span>cfg = <span class="kw">crate</span>::Config::new(<span class="kw">crate</span>::PROTOCOL_VERSION).unwrap(); |
| cfg.set_cc_algorithm(recovery::CongestionControlAlgorithm::BBR); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>r = Recovery::new(<span class="kw-2">&</span>cfg); |
| <span class="kw">let </span>now = Instant::now(); |
| <span class="kw">let </span>mss = r.max_datagram_size; |
| |
| r.on_init(); |
| |
| <span class="comment">// At 4th roundtrip, filled_pipe=true and switch to Drain, |
| // but move to ProbeBW immediately because bytes_in_flight is |
| // smaller than BBRInFlight(1). |
| </span><span class="kw">for </span>(pn, <span class="kw">_</span>) <span class="kw">in </span>(<span class="number">0</span>..<span class="number">4</span>).enumerate() { |
| <span class="kw">let </span>pkt = Sent { |
| pkt_num: pn <span class="kw">as </span>u64, |
| frames: <span class="macro">smallvec!</span>[], |
| time_sent: now, |
| time_acked: <span class="prelude-val">None</span>, |
| time_lost: <span class="prelude-val">None</span>, |
| size: mss, |
| ack_eliciting: <span class="bool-val">true</span>, |
| in_flight: <span class="bool-val">true</span>, |
| delivered: r.delivery_rate.delivered(), |
| delivered_time: now, |
| first_sent_time: now, |
| is_app_limited: <span class="bool-val">false</span>, |
| tx_in_flight: <span class="number">0</span>, |
| lost: <span class="number">0</span>, |
| has_data: <span class="bool-val">false</span>, |
| pmtud: <span class="bool-val">false</span>, |
| }; |
| |
| r.on_packet_sent( |
| pkt, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| ); |
| |
| <span class="kw">let </span>rtt = Duration::from_millis(<span class="number">50</span>); |
| <span class="kw">let </span>now = now + rtt; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>acked = ranges::RangeSet::default(); |
| acked.insert(<span class="number">0</span>..pn <span class="kw">as </span>u64 + <span class="number">1</span>); |
| |
| <span class="macro">assert_eq!</span>( |
| r.on_ack_received( |
| <span class="kw-2">&</span>acked, |
| <span class="number">25</span>, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| <span class="kw-2">&mut </span>Vec::new(), |
| ), |
| <span class="prelude-val">Ok</span>((<span class="number">0</span>, <span class="number">0</span>)), |
| ); |
| } |
| |
| <span class="comment">// Now we are in ProbeBW state. |
| </span><span class="macro">assert!</span>(r.bbr_state.filled_pipe); |
| <span class="macro">assert_eq!</span>(r.bbr_state.state, BBRStateMachine::ProbeBW); |
| |
| <span class="comment">// In the first ProbeBW cycle, pacing_gain should be >= 1.0. |
| </span><span class="macro">assert!</span>(r.bbr_state.pacing_gain >= <span class="number">1.0</span>); |
| } |
| |
| <span class="attr">#[test] |
| </span><span class="kw">fn </span>bbr_probe_rtt() { |
| <span class="kw">let </span><span class="kw-2">mut </span>cfg = <span class="kw">crate</span>::Config::new(<span class="kw">crate</span>::PROTOCOL_VERSION).unwrap(); |
| cfg.set_cc_algorithm(recovery::CongestionControlAlgorithm::BBR); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>r = Recovery::new(<span class="kw-2">&</span>cfg); |
| <span class="kw">let </span>now = Instant::now(); |
| <span class="kw">let </span>mss = r.max_datagram_size; |
| |
| r.on_init(); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>pn = <span class="number">0</span>; |
| |
| <span class="comment">// At 4th roundtrip, filled_pipe=true and switch to Drain, |
| // but move to ProbeBW immediately because bytes_in_flight is |
| // smaller than BBRInFlight(1). |
| </span><span class="kw">for _ in </span><span class="number">0</span>..<span class="number">4 </span>{ |
| <span class="kw">let </span>pkt = Sent { |
| pkt_num: pn, |
| frames: <span class="macro">smallvec!</span>[], |
| time_sent: now, |
| time_acked: <span class="prelude-val">None</span>, |
| time_lost: <span class="prelude-val">None</span>, |
| size: mss, |
| ack_eliciting: <span class="bool-val">true</span>, |
| in_flight: <span class="bool-val">true</span>, |
| delivered: r.delivery_rate.delivered(), |
| delivered_time: now, |
| first_sent_time: now, |
| is_app_limited: <span class="bool-val">false</span>, |
| tx_in_flight: <span class="number">0</span>, |
| lost: <span class="number">0</span>, |
| has_data: <span class="bool-val">false</span>, |
| pmtud: <span class="bool-val">false</span>, |
| }; |
| |
| r.on_packet_sent( |
| pkt, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| ); |
| |
| pn += <span class="number">1</span>; |
| |
| <span class="kw">let </span>rtt = Duration::from_millis(<span class="number">50</span>); |
| <span class="kw">let </span>now = now + rtt; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>acked = ranges::RangeSet::default(); |
| acked.insert(<span class="number">0</span>..pn); |
| |
| <span class="macro">assert_eq!</span>( |
| r.on_ack_received( |
| <span class="kw-2">&</span>acked, |
| <span class="number">25</span>, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| <span class="kw-2">&mut </span>Vec::new(), |
| ), |
| <span class="prelude-val">Ok</span>((<span class="number">0</span>, <span class="number">0</span>)), |
| ); |
| } |
| |
| <span class="comment">// Now we are in ProbeBW state. |
| </span><span class="macro">assert_eq!</span>(r.bbr_state.state, BBRStateMachine::ProbeBW); |
| |
| <span class="comment">// After RTPROP_FILTER_LEN (10s), switch to ProbeRTT. |
| </span><span class="kw">let </span>now = now + RTPROP_FILTER_LEN; |
| |
| <span class="kw">let </span>pkt = Sent { |
| pkt_num: pn, |
| frames: <span class="macro">smallvec!</span>[], |
| time_sent: now, |
| time_acked: <span class="prelude-val">None</span>, |
| time_lost: <span class="prelude-val">None</span>, |
| size: mss, |
| ack_eliciting: <span class="bool-val">true</span>, |
| in_flight: <span class="bool-val">true</span>, |
| delivered: r.delivery_rate.delivered(), |
| delivered_time: now, |
| first_sent_time: now, |
| is_app_limited: <span class="bool-val">false</span>, |
| tx_in_flight: <span class="number">0</span>, |
| lost: <span class="number">0</span>, |
| has_data: <span class="bool-val">false</span>, |
| pmtud: <span class="bool-val">false</span>, |
| }; |
| |
| r.on_packet_sent( |
| pkt, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| ); |
| |
| pn += <span class="number">1</span>; |
| |
| <span class="comment">// Don't update rtprop by giving larger rtt than before. |
| // If rtprop is updated, rtprop expiry check is reset. |
| </span><span class="kw">let </span>rtt = Duration::from_millis(<span class="number">100</span>); |
| <span class="kw">let </span>now = now + rtt; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>acked = ranges::RangeSet::default(); |
| acked.insert(<span class="number">0</span>..pn); |
| |
| <span class="macro">assert_eq!</span>( |
| r.on_ack_received( |
| <span class="kw-2">&</span>acked, |
| <span class="number">25</span>, |
| packet::Epoch::Application, |
| HandshakeStatus::default(), |
| now, |
| <span class="string">""</span>, |
| <span class="kw-2">&mut </span>Vec::new(), |
| ), |
| <span class="prelude-val">Ok</span>((<span class="number">0</span>, <span class="number">0</span>)), |
| ); |
| |
| <span class="macro">assert_eq!</span>(r.bbr_state.state, BBRStateMachine::ProbeRTT); |
| <span class="macro">assert_eq!</span>(r.bbr_state.pacing_gain, <span class="number">1.0</span>); |
| } |
| } |
| |
| <span class="kw">mod </span>init; |
| <span class="kw">mod </span>pacing; |
| <span class="kw">mod </span>per_ack; |
| <span class="kw">mod </span>per_transmit; |
| </code></pre></div></section></main></body></html> |
