Fix documentation for log file growth.
This fixes #546 reported on GitHub.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194549692
diff --git a/doc/impl.md b/doc/impl.md
index 6e6b2ab..cacabb9 100644
--- a/doc/impl.md
+++ b/doc/impl.md
@@ -65,12 +65,14 @@
## Level 0
When the log file grows above a certain size (4MB by default):
-Create a brand new memtable and log file and direct future updates here
+Create a brand new memtable and log file and direct future updates here.
+
In the background:
-Write the contents of the previous memtable to an sstable
-Discard the memtable
-Delete the old log file and the old memtable
-Add the new sstable to the young (level-0) level.
+
+1. Write the contents of the previous memtable to an sstable.
+2. Discard the memtable.
+3. Delete the old log file and the old memtable.
+4. Add the new sstable to the young (level-0) level.
## Compactions
