On Mon, Apr 14, 2014 at 9:42 AM, Borodin Vladimir <r...@simply.name> wrote:
> 14 апр. 2014 г., в 19:11, Jeff Janes <jeff.ja...@gmail.com> написал(а): > > > During the writing phase of the checkpoint, PostgreSQL passes the dirty > data to the OS. At the end, it then tells the OS to make sure that that > data has actually reached disk. If your OS stored up too much dirty data > in memory then it kind of freaks out once it is notified it needs to > actually write that data to disk. The best solution for this may be to > lower dirty_background_bytes or dirty_background_ratio so the OS doesn't > store up so much trouble for itself. > > > Actually, I have already tuned them to different values. Test results > above have been obtained with such settings for page cache: > > vm.dirty_background_ratio = 5 > If you have 64GB of RAM, that is 3.2GB of allowed dirty data, which is probably too much. But I think I've heard rumors that the kernel ignores settings below 5, so probably switch to dirty_background_bytes. Cheers, Jeff
