Re: posix_fadvise noreuse disables file caching

2012-01-31 Thread Rick Macklem
John Baldwin wrote: > On Tuesday, January 31, 2012 12:21:07 pm Ulrich Spörlein wrote: > > On Mon, 2012-01-30 at 09:36:45 -0500, John Baldwin wrote: > > > On Sunday, January 29, 2012 10:08:10 am Tijl Coosemans wrote: > > > > On Wednesday 25 January 2012 17:29:22 John Baldwin wrote: > > > > > On Frid

Re: posix_fadvise noreuse disables file caching

2012-01-31 Thread John Baldwin
On Tuesday, January 31, 2012 12:21:07 pm Ulrich Spörlein wrote: > On Mon, 2012-01-30 at 09:36:45 -0500, John Baldwin wrote: > > On Sunday, January 29, 2012 10:08:10 am Tijl Coosemans wrote: > > > On Wednesday 25 January 2012 17:29:22 John Baldwin wrote: > > > > On Friday, January 20, 2012 2:12:13 p

Re: posix_fadvise noreuse disables file caching

2012-01-31 Thread Ulrich Spörlein
On Mon, 2012-01-30 at 09:36:45 -0500, John Baldwin wrote: > On Sunday, January 29, 2012 10:08:10 am Tijl Coosemans wrote: > > On Wednesday 25 January 2012 17:29:22 John Baldwin wrote: > > > On Friday, January 20, 2012 2:12:13 pm John Baldwin wrote: > > >> On Thursday, January 19, 2012 11:39:42 am T

Re: posix_fadvise noreuse disables file caching

2012-01-30 Thread John Baldwin
On Sunday, January 29, 2012 10:08:10 am Tijl Coosemans wrote: > On Wednesday 25 January 2012 17:29:22 John Baldwin wrote: > > On Friday, January 20, 2012 2:12:13 pm John Baldwin wrote: > >> On Thursday, January 19, 2012 11:39:42 am Tijl Coosemans wrote: > >>> I recently noticed that multimedia/vlc

Re: posix_fadvise noreuse disables file caching

2012-01-29 Thread Tijl Coosemans
On Wednesday 25 January 2012 17:29:22 John Baldwin wrote: > On Friday, January 20, 2012 2:12:13 pm John Baldwin wrote: >> On Thursday, January 19, 2012 11:39:42 am Tijl Coosemans wrote: >>> I recently noticed that multimedia/vlc generates a lot of disk IO when >>> playing media files. For instance,

Re: posix_fadvise noreuse disables file caching

2012-01-25 Thread Julian Elischer
On 1/25/12 8:29 AM, John Baldwin wrote: So I've came up with this untested patch. It uses VOP_ADVISE(FADV_DONTNEED) after read(2) calls to a NOREUSE region, and leaves read-ahead caching enabled for NOREUSE. FADV_DONTNEED doesn't do any good really for writes (it only flushes clean buffers), s

Re: posix_fadvise noreuse disables file caching

2012-01-25 Thread John Baldwin
On Friday, January 20, 2012 2:12:13 pm John Baldwin wrote: > On Thursday, January 19, 2012 11:39:42 am Tijl Coosemans wrote: > > Hi, > > > > I recently noticed that multimedia/vlc generates a lot of disk IO when > > playing media files. For instance, when playing a 320kbps mp3 gstat > > reports ab

Re: posix_fadvise noreuse disables file caching

2012-01-20 Thread John Baldwin
On Thursday, January 19, 2012 11:39:42 am Tijl Coosemans wrote: > Hi, > > I recently noticed that multimedia/vlc generates a lot of disk IO when > playing media files. For instance, when playing a 320kbps mp3 gstat > reports about 1250kBps (=1kbps). That's quite a lot of overhead. > > It turn

posix_fadvise noreuse disables file caching

2012-01-19 Thread Tijl Coosemans
Hi, I recently noticed that multimedia/vlc generates a lot of disk IO when playing media files. For instance, when playing a 320kbps mp3 gstat reports about 1250kBps (=1kbps). That's quite a lot of overhead. It turns out that vlc sets POSIX_FADV_NOREUSE on the entire file and reads in chunks