| commit | 4bb14d4b1be14417e47d0bbaf2bd4e188eda647f | [log] [tgz] |
|---|---|---|
| author | gmarin13 <gmarin13@users.noreply.github.com> | Tue Jul 20 11:47:32 2021 -0700 |
| committer | GitHub <noreply@github.com> | Tue Jul 20 11:47:32 2021 -0700 |
| tree | 94d5b610d24eee4637e1bb02a9598326db7edbd5 | |
| parent | 86eeefc3e4714e359ff19990b871874910636148 [diff] |
Add support for matching split mappings to segments. (#641) * Remove the strict test on segment memory size. It's not precise in some corner cases. It assumes a mapping includes at most one segment, but the loader may map memory for the entire binary at first, and under the right circumstances, this test can select the wrong segment. The filtering by sample offset works more reliably. Also, the strict test on segment memory size is less effective after adding support for matching split mappings to segments. * Add support for matching split mappings to segments. Update ProgramHeadersForMapping to match a mapping to any segment with overlapping file offsets, except if: - if the mapping starts before the page aligned offset associated with a segment. There is no known instance where the loader would load the content of a segment to include preceding pages of the file that don't include any segment content. The mapping must be associated with an earlier segment in such cases. - if the mappings includes the last page of the segment, but not the full segment, and it includes additional pages after the segment end. It's more likely that the mapping is associated with the following segment in such cases.
pprof is a tool for visualization and analysis of profiling data.
pprof reads a collection of profiling samples in profile.proto format and generates reports to visualize and help analyze the data. It can generate both text and graphical reports (through the use of the dot visualization package).
profile.proto is a protocol buffer that describes a set of callstacks and symbolization information. A common usage is to represent a set of sampled callstacks from statistical profiling. The format is described on the proto/profile.proto file. For details on protocol buffers, see https://developers.google.com/protocol-buffers
Profiles can be read from a local file, or over http. Multiple profiles of the same type can be aggregated or compared.
If the profile samples contain machine addresses, pprof can symbolize them through the use of the native binutils tools (addr2line and nm).
This is not an official Google product.
Prerequisites:
Go development kit of a supported version. Follow these instructions to install the go tool and set up GOPATH.
Graphviz: http://www.graphviz.org/ Optional, used to generate graphic visualizations of profiles
To build and install it, use the go get tool.
go get -u github.com/google/pprof
Remember to set GOPATH to the directory where you want pprof to be installed. The binary will be in $GOPATH/bin and the sources under $GOPATH/src/github.com/google/pprof.
pprof can read a profile from a file or directly from a server via http. Specify the profile input(s) in the command line, and use options to indicate how to format the report.
% pprof -top [main_binary] profile.pb.gz
Where
main_binary: Local path to the main program binary, to enable symbolization
profile.pb.gz: Local path to the profile in a compressed protobuf, or
URL to the http service that serves a profile.
pprof -web [main_binary] profile.pb.gz
If no output formatting option is specified, pprof runs on interactive mode, where reads the profile and accepts interactive commands for visualization and refinement of the profile.
pprof [main_binary] profile.pb.gz This will open a simple shell that takes pprof commands to generate reports. Type 'help' for available commands/options.
If the -http flag is specified, pprof starts a web server at the specified host:port that provides an interactive web-based interface to pprof. Host is optional, and is “localhost” by default. Port is optional, and is a random available port by default. -http=":" starts a server locally at a random port.
pprof -http=[host]:[port] [main_binary] profile.pb.gz
The preceding command should automatically open your web browser at the right page; if not, you can manually visit the specified port in your web browser.
pprof can read perf.data files generated by the Linux perf tool by using the perf_to_profile program from the perf_data_converter package.
To view disassembly of profiles collected from Go programs compiled as Windows executables, the executable must be built with go build -buildmode=exe. LLVM or GCC must be installed, so required tools like addr2line and nm are available to pprof.
See doc/README.md for more detailed end-user documentation.
See CONTRIBUTING.md for contribution documentation.
See proto/README.md for a description of the profile.proto format.