search for: arc_max

Hello, Im about to migrate a 6Tb database from Veritas Volume Manager to ZFS, I want to set arc_max parameter so ZFS cant use all my system''s memory, but i dont know how much i should set, do you think 24Gb will be enough for a 6Tb database? obviously the more the better but i cant set too much memory. Have someone implemented succesfully something similar? We ran some test and the usag...

Hello All, Awhile back (Feb ''07) when we noticed ZFS was hogging all the memory on the system, y''all were kind enough to help us use the arc_max tunable to attempt to limit that usage to a hard value. Unfortunately, at the time a sticky problem was that the hard limit did not include DNLC entries generated by ZFS. I''ve been watching the list since then and trying to watch the Nevada commits. I haven''t noticed that anythin...

I gave the AMD64 version of 7.2 RC2 a spin and all installed as expected off the dvd INTEL S3200SHV MB, Core2Duo, 4G of RAM In the past it had been suggested that for zfs tuning, something like vm.kmem_size_max="1073741824" vm.kmem_size="1073741824" vfs.zfs.prefetch_disable=1 However doing a simple test with bonnie and dd, there does not seem to be very much difference in

...s stop working for a few seconds, except one disk at a time. When this cycle is finished, it looks normal again. This seems to be the flushing of the NVRAM cache. Should be solved by disabling the flush...So far so good... But I also need the memory for PostgreSQL to work, so I added: set zfs:zfs_arc_max=8589934592 to /etc/system and rebooted. Now redid my test, with terrible results.. sequential read is about 120 MB/sec. One disk should be able to handle that, 14 disks should do more than a GB/sec, and in my previous benchmark without the arc_max setting, they actually make these figures...(even...

Hello zfs question about memory. I heard zfs is very ram hungry. Service looking to run: - nginx - postgres - php-fpm - python I have a machine with two quad core cpus but only 4 G Memory I'm looking to buy more ram now. What would be the recommend amount of memory for zfs across 6 drives on this setup? Also can 9.1 now boot to zfs from the installer? (no tricks for post install) Thanks

Hi, could anyone give recommendations (or share experience) regarding using ZFS: - FreeBSD 7-Stable (amd64 with 8GB RAM) + special tuning necessary (apart from increasing kernel memory to 1 or more GB for ZFS) - Samba 3.2 + ACLs possible directly under ZFS? + recommended compile options? - NFS - email (imap) - jails (I have seen some problems exist with using snaphots within

Hi. I''m all set for doing performance comparsion between Solaris/ZFS and FreeBSD/ZFS. I spend last few weeks on FreeBSD/ZFS optimizations and I think I''m ready. The machine is 1xQuad-core DELL PowerEdge 1950, 2GB RAM, 15 x 74GB-FC-10K accesses via 2x2Gbit FC links. Unfortunately the links to disks are the bottleneck, so I''m going to use not more than 4 disks, probably.

...-zfs-rrws10m-Mar_2_2010-03h_10m_46s/rr32k/stats.rr32k.out ------------------------------------------------------------------------------------------------ The output for the same workload is disappointing , notice that the throughput dropped from 1307.7 mb/s to 2.7 mb/s !!!!!!!!!!!!!!!!!!!!!!1 My ARC_max is 3G Here is a snapshot of my arcstat output in case of high throughput --- notice the 100% hits ratio arcsz,read,hits,Hit%,miss,miss%,dhit,dh%,dmis,dm%,phit,ph%,pmis,pm%,mhit,mh%,mmis,mm%,mfug,mrug, 1G, 31M, 31M, 99,111K, 0, 28M, 99, 99K, 0, 2M, 99, 12K, 0, 1M, 98, 13K, 1, 43, 43...

Hello A box of mine running RELENG_7_0 and ZFS over a couple of disks (6 disks, 3 mirrors) seems to have gotten stuck. From Ctrl-T: load: 0.50 cmd: zsh 40188 [zfs:&buf_hash_table.ht_locks[i].ht_lock] 0.02u 0.04s 0% 3404k load: 0.43 cmd: zsh 40188 [zfs:&buf_hash_table.ht_locks[i].ht_lock] 0.02u 0.04s 0% 3404k load: 0.10 cmd: zsh 40188 [zfs:&buf_hash_table.ht_locks[i].ht_lock]

We are using MySQL, and love the idea of using zfs for this. We are used to using Direct I/O to bypass file system caching (let the DB do this). Does this exist for zfs? This message posted from opensolaris.org