That doesn't sound right. SQLite's lock for writes is not the best, but it is still pthread mutex under the hood. Are you sure your compilation options for SQLite is right? One common pitfall is compiling without `-DHAVE_USLEEP`. In absence of that flag, SQLite will use sleep in case of conflict, and that will have time resolution of 1 second, causing 1s delay on every lock contention. That flag tells SQLite to use usleep instead, and it is substantially faster on busy timeout.

Here is my SQLite compilation flags: https://github.com/liuliu/dflat/blob/unstable/external/sqlit...

Here is where the flag used: https://github.com/sqlite/sqlite/blob/d46beb06aab941bf165a9d...