[issue18816] mmap.flush() is always synchronous, hurting performance

Changes by Josh Rosenberg shadowranger+pyt...@gmail.com: -- nosy: +josh.rosenberg ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue18816 ___ ___

[issue18816] mmap.flush() is always synchronous, hurting performance

Charles-François Natali added the comment: I propose to add an optional keyword parameter with default value SYNC (compatibility) but that can be ASYNC, INVALIDATE (can be SYNC|INVALIDATE and ASYNC|INVALIDATE too). AFAICT it's mostly useless on a modern OS. MS_INVALIDATE is a no-op on

[issue18816] mmap.flush() is always synchronous, hurting performance

Jesús Cea Avión added the comment: Depending of a concrete OS implementation is not good. Linux is not the only OS out there, and I have very old machines in production yet: # uname -a Linux colquide..es 2.4.37 #4 Fri Dec 12 01:10:45 CET 2008 i686 unknown I have been hit by the VM/file

[issue18816] mmap.flush() is always synchronous, hurting performance

New submission from Jesús Cea Avión: Currently, mmap.flush() does a synchronous write to the backend file. The call will wait until data is actually flushed to disk, because internally it is doing a msync(MS_SYNC). But the value of mmap.flush() is to synchronize file and memory. You don't