On Tue, Jan 24, 2012 at 09:39:36PM +0100, Jan Kara wrote: > On Tue 24-01-12 15:13:40, Jeff Moyer wrote: [snip] > > > Maybe 128 KB is a too small default these days but OTOH noone prevents you > > > from raising it (e.g. SLES uses 1 MB as a default). > > > > For some reason, I thought it had been bumped to 512KB by default. Must > > be that overactive imagination I have... Anyway, if all of the distros > > start bumping the default, don't you think it's time to consider bumping > > it upstream, too? I thought there was a lot of work put into not being > > too aggressive on readahead, so the downside of having a larger > > read_ahead_kb setting was fairly small. > Yeah, I believe 512KB should be pretty safe these days except for > embedded world. OTOH average desktop user doesn't really care so it's > mostly servers with beefy storage that care... (note that I wrote we raised > the read_ahead_kb for SLES but not for openSUSE or SLED (desktop enterprise > distro)). Maybe we don't need to care much about the embedded world when raising the default readahead size? Because even the current 128KB is too much for them, and I see Android setting the readahead size to 4KB... Some time ago I posted a series for raising the default readahead size to 512KB. But I'm open to use 1MB now (shall we vote on it?). Thanks, Fengguang -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
