[sqlite] Why SQLite use busy-retry but not lock-and-wait?

[Simon Slavin]

On 6 Apr 2016, at 5:03am, sanhua.zh <sanhua.zh at foxmail.com> wrote:

> I found that on OS level, SQLite use file lock to solve multi-processes 
> problem and use VFS to solve multi-threads problem. But all of them might 
> failed with racing and SQLite will return a SQLITE_BUSY result code to make 
> it sleep-and-retry.

Use this call

<https://www.sqlite.org/c3ref/busy_timeout.html>

To tell SQLite to handle backoff-and-retry itself.

Simon.