On Fri December 16 2011, Herbert Poetzl wrote: > On Mon, Dec 12, 2011 at 03:55:40PM +0100, Eugen Leitl wrote: > > On Mon, Dec 12, 2011 at 08:22:07AM -0600, Michael S. Zick wrote: > > >> Why not use a small SATA-3 SSD on each of the host machines > >> as a cache in front of your network file or block system? > > > If I would be running Solaris on my boxes I would do just > > that (notice that I have only 2 SATA slots on the system, > > so there's no space for another drive once you go > > RAID 1). However, as a vserver user, my options are limited > > to the fs that Linux natively provides. So no SSD caching > > for me, until btrfs goes production, and actually can deal > > with SSDs intelligently. > > hmm ... > > CONFIG_FSCACHE: > > This option enables a generic filesystem caching manager that can be > used by various network and other filesystems to cache data locally. > Different sorts of caches can be plugged in, depending on the > resources available. > > See Documentation/filesystems/caching/fscache.txt for more information. > > Symbol: FSCACHE [=n] > Type : tristate > Prompt: General filesystem local caching manager > Defined at fs/fscache/Kconfig:2 > Location: > -> File systems > -> Caches > > CONFIG_CACHEFILES: > > This permits use of a mounted filesystem as a cache for other > filesystems - primarily networking filesystems - thus allowing fast > local disk to enhance the speed of slower devices. > > See Documentation/filesystems/caching/cachefiles.txt for more > information. > > Symbol: CACHEFILES [=n] > Type : tristate > Prompt: Filesystem caching on files > Defined at fs/cachefiles/Kconfig:2 > Depends on: FSCACHE [=y] && BLOCK [=y] > Location: > -> File systems > -> Caches > -> General filesystem local caching manager (FSCACHE [=y]) > > CONFIG_NFS_FSCACHE: > > Say Y here if you want NFS data to be cached locally on disc through > the general filesystem cache manager > > Symbol: NFS_FSCACHE [=n] > Type : boolean > Prompt: Provide NFS client caching support > Defined at fs/nfs/Kconfig:112 > Depends on: NETWORK_FILESYSTEMS [=y] && (NFS_FS [=y]=m && FSCACHE [=y] || NFS_FS [=y]=y && FSCACHE [=y]=y) > Location: > -> File systems > -> Network File Systems (NETWORK_FILESYSTEMS [=y]) > > not sure what solaris would do 'better' here ... > Thank you for looking that up. I knew it was all in the kernel (somewhere), just did not have the time to look it up myself. ;-) Guess I better bookmark this post so I don't loose the information (again). Mike > best, > Herbert > > >> Something like: > >> http://www.kingston.com/ssd/kc100.asp > > >> Which would (in the 120Gbyte size) run you about $2/Gbyte and > >> give each client machine a local 90K IOPS cache in front of > >> your old server network connected at only 1Gbs. > >> Caching locally about 5% of the network data would greatly > >> reduce your network load. > > >> Unless you can upgrade your networking to 10Gbs fiber, I think > >> this would give you about the next best performance. > > >> Mike > >>> I think I'll go with an NFS. I have some 3 consumer NAS > >>> which export NFS as well, and I haven't done iSCSI yet > >>> so NFS is definitely simpler to deploy. > > > > -- > > Eugen* Leitl <a href="leitlhttp://leitl.org">leitl</a> http://leitl.org > > ______________________________________________________________ > > ICBM: 48.07100, 11.36820 http://www.ativel.com http://postbiota.org > > 8B29F6BE: 099D 78BA 2FD3 B014 B08A 7779 75B0 2443 8B29 F6BE > >