Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
> I'm currently planning on running FreeBSD with ZFS, but I wanted to > double-check how much memory I'd need for it to be stable. The ZFS > wiki currently says you can go as low as 1 GB, but recommends 2 GB; > however, elsewhere I've seen someone claim that you need at least 4 GB. > ... > How about other OpenSolaris-based OSs, like NexentaStor? > ... > If it matters, I'm currently planning on RAID-Z2 with 4x500GB > consumer-grade SATA drives. ... This is on an AMD64 system, > and the OS in question will be running inside of VirtualBox ... > Thanks, > Michael > Buy the biggest Chips you can afford and if you need to pair them (for performance) do so. You want to keep as many Memory Slots open as you can so you can add more memory later. I think you (or I) would be unhappy with a measly 4GB in a new System but in reality it would be OK. If it is not OK (for you) then you have open Memory Slots in which to add more Chips (which you are certain to want to do in the future). Rob -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
On 2010-Jul-19 07:15:45 +0800, Richard Elling wrote: >On Jul 18, 2010, at 3:40 PM, Peter Jeremy wrote: >> 3.5GB. Note that in any case, patching ARC to work around the out- >> of-free-memory bug is fairly important. > >Do you have a CR for this bug? This is a FreeBSD-specific bug related to interaction between ZFS ARC and the FreeBSD VM - it's not a ZFS bug. It's fairly clearly described in http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/146410 but there are a number of other open PRs that describe similar problems. -- Peter Jeremy pgpXO7CznTo5y.pgp Description: PGP signature ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
On Jul 18, 2010, at 3:40 PM, Peter Jeremy wrote: > On 2010-Jul-17 01:24:57 +0800, Michael Johnson > wrote: >> I'm currently planning on running FreeBSD with ZFS, but I wanted to >> double-check >> how much memory I'd need for it to be stable. The ZFS wiki currently says >> you >> can go as low as 1 GB, but recommends 2 GB; however, elsewhere I've seen >> someone >> claim that you need at least 4 GB. Does anyone here know how much RAM >> FreeBSD >> would need in this case? > > I am running FreeBSD 8.x with ZFS on several systems. From my > experiences, 2GB is a bare minimum and it seems a lot happier with > 3.5GB. Note that in any case, patching ARC to work around the out- > of-free-memory bug is fairly important. Do you have a CR for this bug? -- richard -- ZFS and performance consulting http://www.RichardElling.com ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
On 2010-Jul-17 01:24:57 +0800, Michael Johnson wrote: >I'm currently planning on running FreeBSD with ZFS, but I wanted to >double-check >how much memory I'd need for it to be stable. The ZFS wiki currently says you >can go as low as 1 GB, but recommends 2 GB; however, elsewhere I've seen >someone >claim that you need at least 4 GB. Does anyone here know how much RAM FreeBSD >would need in this case? I am running FreeBSD 8.x with ZFS on several systems. From my experiences, 2GB is a bare minimum and it seems a lot happier with 3.5GB. Note that in any case, patching ARC to work around the out- of-free-memory bug is fairly important. >Likewise, how much RAM does OpenSolaris need for stability when running ZFS? I have a SPARC OSol system that seemed OK with 2GB, though I never really stres it. -- Peter Jeremy pgpXoS8zJe7fq.pgp Description: PGP signature ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
"Sam Fourman Jr." wrote: > using FreeBSD 9 w/ ZFSv15 using default settings, nothing in loader.conf > or nothing in sysctl.conf and a GENERIC kernel > > 12GB of memory seems to be all ZFS wanted to use, I have tried > machines with 32GB > but zfs never wants to use more unless you play with loader.conf settings On Solaris on a SunFire X4540 with 64 GB, I've seen ZFS RAM usage far beyond 32 GB without doing anything. Do you know whether this FreeBSD behavior is intended? Jörg -- EMail:jo...@schily.isdn.cs.tu-berlin.de (home) Jörg Schilling D-13353 Berlin j...@cs.tu-berlin.de(uni) joerg.schill...@fokus.fraunhofer.de (work) Blog: http://schily.blogspot.com/ URL: http://cdrecord.berlios.de/private/ ftp://ftp.berlios.de/pub/schily ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
On Fri, Jul 16, 2010 at 12:24 PM, Michael Johnson wrote: > I'm currently planning on running FreeBSD with ZFS, but I wanted to > double-check > how much memory I'd need for it to be stable. The ZFS wiki currently says you > can go as low as 1 GB, but recommends 2 GB; however, elsewhere I've seen > someone > claim that you need at least 4 GB. Does anyone here know how much RAM FreeBSD > would need in this case? > > Likewise, how much RAM does OpenSolaris need for stability when running ZFS? > How about other OpenSolaris-based OSs, like NexentaStor? (My searching found > that OpenSolaris recommended at least 1 GB, while NexentaStor said 2 GB was > okay, 4 GB was better. I'd be interested in hearing your input, though.) > > If it matters, I'm currently planning on RAID-Z2 with 4x500GB consumer-grade > SATA drives. (I know that's not a very efficient configuration, but I'd > really > like the redundancy of RAID-Z2 and I just don't need more than 1 TB of > available > storage right now, or for the next several years.) This is on an AMD64 > system, > and the OS in question will be running inside of VirtualBox, with raw access > to > the drives. > > Thanks, > Michael > using FreeBSD 9 w/ ZFSv15 using default settings, nothing in loader.conf or nothing in sysctl.conf and a GENERIC kernel 12GB of memory seems to be all ZFS wanted to use, I have tried machines with 32GB but zfs never wants to use more unless you play with loader.conf settings if I was building a small office NAS 12GB would be where I would start. I run mostly whitebox hardware (asus motherboards desktop disks etc..) in my experience, I have found FreeBSD to be much more stable than Open Solaris but to be fair, I understand FreeBSD, and I have only loaded Open solaris with default settings and the most ram I ever gave open Solaris is a 8GB machine so if you wanted to go with Open solaris (for dedupe and such) I would use a Lot of ram from many people I have talked to 32GB of memory and Open Soalris is really stable -- Sam Fourman Jr. Fourman Networks http://www.fourmannetworks.com ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
On Fri, 16 Jul 2010, Michael Johnson wrote: Just curious, why do you say I'd be able to get away with less RAM in FreeBSD (as compared to NexentaStor, I'm assuming)? I don't know tons about the OSs in question; is FreeBSD just leaner in general? The FreeBSD OS itself is normally leaner but FreeBSD plus zfs is not (yet) as memory efficient as Solaris. Solaris and zfs do the Vulcan mind-meld when it comes to memory but FreeBSD does not. Bob -- Bob Friesenhahn bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer,http://www.GraphicsMagick.org/ ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
On Fri, 2010-07-16 at 11:57 -0700, Michael Johnson wrote: > us, why do you say I'd be able to get away with less RAM in FreeBSD > (as compared to NexentaStor, I'm assuming)? I don't know tons about > the OSs in > question; is FreeBSD just leaner in general? Compared to Solaris, in my estimation, yes, its a little leaner. Not necessarily a lot -- the bulk of memory consumption these days is ZFS and applications (Firefox!) - Garrett ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
On Fri, Jul 16, 2010 at 10:24 AM, Michael Johnson wrote: > I'm currently planning on running FreeBSD with ZFS, but I wanted to > double-check > how much memory I'd need for it to be stable. The ZFS wiki currently says you > can go as low as 1 GB, but recommends 2 GB; however, elsewhere I've seen > someone > claim that you need at least 4 GB. Does anyone here know how much RAM FreeBSD > would need in this case? There's no such thing as "too much RAM" when it comes to ZFS. The more RAM you add to the system, the better it will perform. ZFS will use all the RAM you give it for the ARC, enabling it to cache more and more data. On the flip side, if you spend enough time tuning ZFS and FreeBSD, you can use ZFS on a system with 512 MB of RAM (there are reports on the FreeBSD mailing lists of various people doing thing on single-drive laptops). However, the "rule of thumb" for ZFS is 2 GB of RAM as a bare minimum, using the 64-bit version of FreeBSD. The "sweet spot" is 4 GB of RAM. But, more is always better. -- Freddie Cash fjwc...@gmail.com ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
Garrett D'Amore wrote: >On Fri, 2010-07-16 at 10:24 -0700, Michael Johnson wrote: >> I'm currently planning on running FreeBSD with ZFS, but I wanted to >>double-check >> how much memory I'd need for it to be stable. The ZFS wiki currently says >you >> can go as low as 1 GB, but recommends 2 GB; however, elsewhere I've seen >>someone >> claim that you need at least 4 GB. Does anyone here know how much RAM >FreeBSD >> would need in this case? >> >> Likewise, how much RAM does OpenSolaris need for stability when running ZFS? >> How about other OpenSolaris-based OSs, like NexentaStor? (My searching >found >> that OpenSolaris recommended at least 1 GB, while NexentaStor said 2 GB was >> okay, 4 GB was better. I'd be interested in hearing your input, though.) > >1GB isn't enough for a real system. 2GB is a bare minimum. If you're >going to use dedup, plan on a *lot* more. I think 4 or 8 GB are good >for a typical desktop or home NAS setup. With FreeBSD you may be able >to get away with less. (Probably, in fact.) Fortunately, I don't need deduplication; it's kind of a nice feature, but the extra RAM it would take isn't worth it. Just curious, why do you say I'd be able to get away with less RAM in FreeBSD (as compared to NexentaStor, I'm assuming)? I don't know tons about the OSs in question; is FreeBSD just leaner in general? >> If it matters, I'm currently planning on RAID-Z2 with 4x500GB consumer-grade >> SATA drives. (I know that's not a very efficient configuration, but I'd >>really >> like the redundancy of RAID-Z2 and I just don't need more than 1 TB of >>available >> storage right now, or for the next several years.) This is on an AMD64 >>system, >> and the OS in question will be running inside of VirtualBox, with raw access >>to >> the drives. > >Btw, instead of RAIDZ2, I'd recommend simply using stripe of mirrors. >You'll have better performance, and good resilience against errors. And >you can grow later as you need to by just adding additional drive pairs. A pair of mirrors would be nice, but would only protect against 100% of one drive failing, and 50% of two-drive failures. Performance is less important to me than redundancy; this setup won't be seeing tons of disk activity, but I want it to be as reliable as possible. Michael ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
Garrett D'Amore wrote: Btw, instead of RAIDZ2, I'd recommend simply using stripe of mirrors. You'll have better performance, and good resilience against errors. And you can grow later as you need to by just adding additional drive pairs. -- Garrett Or in my case, I find my home data growth is slightly less than the rate of disk capacity increase, so every 18 months or so, I simply swap out the disks for higher capacity ones. -- Andrew Gabriel ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Recommended RAM for ZFS on various platforms
1GB isn't enough for a real system. 2GB is a bare minimum. If you're going to use dedup, plan on a *lot* more. I think 4 or 8 GB are good for a typical desktop or home NAS setup. With FreeBSD you may be able to get away with less. (Probably, in fact.) Btw, instead of RAIDZ2, I'd recommend simply using stripe of mirrors. You'll have better performance, and good resilience against errors. And you can grow later as you need to by just adding additional drive pairs. -- Garrett On Fri, 2010-07-16 at 10:24 -0700, Michael Johnson wrote: > I'm currently planning on running FreeBSD with ZFS, but I wanted to > double-check > how much memory I'd need for it to be stable. The ZFS wiki currently says > you > can go as low as 1 GB, but recommends 2 GB; however, elsewhere I've seen > someone > claim that you need at least 4 GB. Does anyone here know how much RAM > FreeBSD > would need in this case? > > Likewise, how much RAM does OpenSolaris need for stability when running ZFS? > How about other OpenSolaris-based OSs, like NexentaStor? (My searching > found > that OpenSolaris recommended at least 1 GB, while NexentaStor said 2 GB was > okay, 4 GB was better. I'd be interested in hearing your input, though.) > > If it matters, I'm currently planning on RAID-Z2 with 4x500GB consumer-grade > SATA drives. (I know that's not a very efficient configuration, but I'd > really > like the redundancy of RAID-Z2 and I just don't need more than 1 TB of > available > storage right now, or for the next several years.) This is on an AMD64 > system, > and the OS in question will be running inside of VirtualBox, with raw access > to > the drives. > > Thanks, > Michael > > > > ___ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss > ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
