Hi, this says that opensolaris only requires 512MB ram: http://dlc.sun.com/osol/docs/content/IPS/sysreq.html This says 1GB ram and a 64bit processor are recommended: http://www.solarisinternals.com/wiki/index.php/ZFS_Best_Practices_Guide#Memory_and_Swap_Space Am I going to have problems if I run opensolaris and zfs at the minimum requirements? -- This message posted from opensolaris.org
On Sun, Sep 14, 2008 at 1:37 PM, MC <rac at eastlink.ca> wrote:> Hi, this says that opensolaris only requires 512MB ram: > http://dlc.sun.com/osol/docs/content/IPS/sysreq.html > > This says 1GB ram and a 64bit processor are recommended: > http://www.solarisinternals.com/wiki/index.php/ZFS_Best_Practices_Guide#Memory_and_Swap_Space > > Am I going to have problems if I run opensolaris and zfs at the minimum > requirements? > -- > This message posted from opensolaris.org > _______________________________________________ > zfs-discuss mailing list > zfs-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss >Yes. ZFS likes ram... a LOT. I would strongly suggest not skimping on Ram, the performance will most likely be horrible. You also really do want a 64bit processor, it makes a difference as well. --Tim -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.opensolaris.org/pipermail/zfs-discuss/attachments/20080914/b5e4b70c/attachment.html>
Tim <tim <at> tcsac.net> writes:> > Yes.? ZFS likes ram... a LOT.? I would strongly suggest not skimping on Ram,the performance will most likely be horrible. You can''t make vague statements like that. Define "performance". My home ZFS server runs with only 1 GB of RAM. It achieves 430 MB/s sequential reads and 220 MB/s writes. This is very good, given that its primary task is to serve large files over NFS. To the OP: 512 MB or 1 GB are sometimes plenty sufficient. What are your needs ? -marc
On Sun, Sep 14, 2008 at 3:34 PM, Marc Bevand <m.bevand at gmail.com> wrote:> You can''t make vague statements like that. Define "performance". > > My home ZFS server runs with only 1 GB of RAM. It achieves 430 MB/s sequential > reads and 220 MB/s writes. This is very good, given that its primary task is > to serve large files over NFS.would you share the rest of your configuation?
On Sun, Sep 14, 2008 at 5:34 PM, Marc Bevand <m.bevand at gmail.com> wrote:> Tim <tim <at> tcsac.net> writes: > > > >> > Yes. ZFS likes ram... a LOT. I would strongly suggest not skimping on >> Ram, >> the performance will most likely be horrible. >> >> You can''t make vague statements like that. Define "performance". >> >> My home ZFS server runs with only 1 GB of RAM. It achieves 430 MB/s >> sequential >> reads and 220 MB/s writes. This is very good, given that its primary task >> is >> to serve large files over NFS. >> >> To the OP: 512 MB or 1 GB are sometimes plenty sufficient. What are your >> needs ? >> >> -marc >> >> _______________________________________________ >> zfs-discuss mailing list >> zfs-discuss at opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss >> > >What part of "performance" is there to define? Your read/write speeds will suck. 1GB ram is a far, far cry from 512. You''re talking about the difference between having just enough ram to run the OS, and having 512MB of ram available for zfs for caching. Telling him he''ll be fine with 512 is an outright lie. There''s post after post on these forums with people wondering why things are horribly slow using small amounts of ram. When it''s 25$ or less for a gig of ram there''s no reason to skimp, period. --Tim -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.opensolaris.org/pipermail/zfs-discuss/attachments/20080914/acd2688c/attachment.html>
mike <mike503 <at> gmail.com> writes:> > On Sun, Sep 14, 2008 at 3:34 PM, Marc Bevand <m.bevand at gmail.com> wrote: > > > My home ZFS server runs with only 1 GB of RAM. It achieves 430 MB/s > > sequential reads and 220 MB/s writes. > > would you share the rest of your configuation?Sure: http://opensolaris.org/jive/thread.jspa?threadID=54481 -marc
Tim <tim <at> tcsac.net> writes:> > What part of "performance" is there to define? Your read/write speeds > will suck."speed" is another vague term. Do you mean throughput, or latency. Local I/O, or over NFS. Etc. FYI a small amount of RAM usually impacts random I/O workloads when they would otherwise fit in memory, but does not reduce the throughput of sequential I/O because prefetching algorithms work just fine as all they need is a few tens of MB of memory.> 1GB ram is a far, far cry from 512. You''re talking about the difference > between having just enough ram to run the OS, and having 512MB of ram > available for zfs for caching. Telling him he''ll be fine with 512 is > an outright lie.As a matter of fact, until march 2008 I had been running snv_55b for over a year with only 512 MB to serve a 2.0-TB pool over NFS. Again, the performances (throughput) were very acceptable. If that''s what the OP needs, then 512 MB would be *technically* sufficient, even if given the current prices 1 GB would make more sense. -marc
Hi all, Depends on the workload, for example for write sync (NFS), adding SSD or iRAM as ZIL (logzilla) probably give a better write throughput compare to add RAM. Also adding SSD as L2ARC (readzilla) probably give better throughput (with same amount of money) rather than adding RAM. Not to mention that SSD will require a lot less power than RAM. Regards, Andre W. Marc Bevand wrote:> Tim <tim <at> tcsac.net> writes: > >> What part of "performance" is there to define? Your read/write speeds >> will suck. >> > > "speed" is another vague term. Do you mean throughput, or latency. Local I/O, > or over NFS. Etc. FYI a small amount of RAM usually impacts random I/O > workloads when they would otherwise fit in memory, but does not reduce the > throughput of sequential I/O because prefetching algorithms work just fine as > all they need is a few tens of MB of memory. > > >> 1GB ram is a far, far cry from 512. You''re talking about the difference >> between having just enough ram to run the OS, and having 512MB of ram >> available for zfs for caching. Telling him he''ll be fine with 512 is >> an outright lie. >> > > As a matter of fact, until march 2008 I had been running snv_55b for over a > year with only 512 MB to serve a 2.0-TB pool over NFS. Again, the performances > (throughput) were very acceptable. If that''s what the OP needs, then 512 MB > would be *technically* sufficient, even if given the current prices 1 GB would > make more sense. > > -marc > > > _______________________________________________ > zfs-discuss mailing list > zfs-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss >
Just one more things on this: Run with a 64-bit processor. Don''t even think of using a 32-bit one - there are known issues with ZFS not quite properly using 32-bit only structures. That is, ZFS is really 64-bit clean, but not 32-bit clean. <grin> -- Erik Trimble Java System Support Mailstop: usca22-123 Phone: x17195 Santa Clara, CA Timezone: US/Pacific (GMT-0800)
On Wed, Sep 17, 2008 at 6:06 AM, Erik Trimble <Erik.Trimble at sun.com> wrote:> Just one more things on this: > > Run with a 64-bit processor. Don''t even think of using a 32-bit one - > there are known issues with ZFS not quite properly using 32-bit only > structures. That is, ZFS is really 64-bit clean, but not 32-bit clean. >Wow ! That''s a statement. Can you provide more info on these 32-bit issues ? I am not aware of any. In fact besides being sluggish (presumably due to limited address space) I never noticed any issues with ZFS, which I used on 32-bit machine for 2 years.> <grin> > > > -- > Erik Trimble > Java System Support > Mailstop: usca22-123 > Phone: x17195 > Santa Clara, CA > Timezone: US/Pacific (GMT-0800) > > _______________________________________________ > zfs-discuss mailing list > zfs-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss >-- Regards, Cyril
Cyril Plisko wrote:> On Wed, Sep 17, 2008 at 6:06 AM, Erik Trimble <Erik.Trimble at sun.com> wrote: > >> Just one more things on this: >> >> Run with a 64-bit processor. Don''t even think of using a 32-bit one - >> there are known issues with ZFS not quite properly using 32-bit only >> structures. That is, ZFS is really 64-bit clean, but not 32-bit clean. >> >> > > Wow ! That''s a statement. Can you provide more info on these 32-bit issues ? > I am not aware of any. In fact besides being sluggish (presumably due > to limited address space) I never noticed any issues with ZFS, which I > used on 32-bit machine for 2 years. > >http://www.opensolaris.org/jive/thread.jspa?messageID=212508𳸜 Looking through the Bug database, it seems that a good chunk of 32-bit-related problems have been resolved. However, there hasn''t been a general fix for the overall issue noted in the above discussion. -- Erik Trimble Java System Support Mailstop: usca22-123 Phone: x17195 Santa Clara, CA Timezone: US/Pacific (GMT-0800)