similar to: quick overhead sizing for DDT and L2ARC

Hi, Created a zpool with 64k recordsize and enabled dedupe on it. zpool create -O recordsize=64k TestPool device1 zfs set dedup=on TestPool I copied files onto this pool over nfs from a windows client. Here is the output of zpool list Prompt:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT TestPool 696G 19.1G 677G 2% 1.13x ONLINE - When I ran a

I''m running a mirrored pair of 2 TB SATA drives as my data storage drives on my home workstation, a Core i7-based machine with 10 GB of RAM. I recently added a sandforce-based 60 GB SSD (OCZ Vertex 2, NOT the pro version) as an L2ARC to the single mirrored pair. I''m running B134, with ZFS pool version 22, with dedup enabled. If I understand correctly, the dedup table should be in

Not sure what the best list to send this to is right now, so I have selected a few, apologies in advance. A couple questions. First I have a physical host (call him bob) that was just installed with b134 a few days ago. I upgraded to b145 using the instructions on the Illumos wiki yesterday. The pool has been upgraded (27) and the zfs file systems have been upgraded (5). chris at bob:~# zpool

Not sure what the best list to send this to is right now, so I have selected a few, apologies in advance. A couple questions. First I have a physical host (call him bob) that was just installed with b134 a few days ago. I upgraded to b145 using the instructions on the Illumos wiki yesterday. The pool has been upgraded (27) and the zfs file systems have been upgraded (5). chris at bob:~# zpool

I have some questions about the choice of SSDs to use for ZIL and L2ARC. I''m trying to build an OpenSolaris iSCSI SAN out of a whitebox system, which is intended to be used as a backup SAN during storage migration, so it''s built on a tight budget. The system currently has 4GB RAM, 3GHz Core2-Quad and 8x 500GB WD REII SATA HDDs attached to an Areca 8port ARC-1220 controller

Hello all, I am not sure my original mail got through to the list (I haven''t received it back), so I attach it below. Anyhow, now I have a saved kernel crash dump of the system panicking when it tries to - I believe - deferred-release the corrupted deduped blocks which are no longer referenced by the userdata/blockpointer tree. As I previously wrote in my thread on unfixeable

I tried the deduplication feature but the performance of my fileserver dived from writing 50MB/s via CIFS to 4MB/s. what happens to the deduped blocks when you set dedup=off? are they written back to disk? is the deduptable deleted or is it still there? thanks -- This message posted from opensolaris.org

After multiple power outages caused by storms coming through, I can no longer access /dev/zvol/dsk/poolname, which are hold l2arc and slog devices in another pool I don''t think this is related, since I the pools are ofline pending access to the volumes. I tried running find /dev/zvol/dsk/poolname -type f and here is the stack, hopefully this someone a hint at what the issue is, I have

I see in NexentaStor''s announcement of Community Edition 3.0.3 they mention some backported patches in this release. Aside from their management features / UI what is the core OS difference if we move to Nexenta from OpenSolaris b134? These DeDup bugs are my main frustration - if a staff member does a rm * in a directory with dedup you can take down the whole storage server - all with

We are looking into the possibility of adding a dedicated ZIL and/or L2ARC devices to our pool. We are looking into getting 4 ? 32GB Intel X25-E SSD drives. Would this be a good solution to slow write speeds? We are currently sharing out different slices of the pool to windows servers using comstar and fibrechannel. We are currently getting around 300MB/sec performance with 70-100% disk busy.

Hello all, A few months ago I saw a statement that L2ARC writes are simplistic in nature, and I got the (mis?)understanding that some sort of ring buffer may be in use, like for ZIL. Is this true, and the only metric of write-performance important for L2ARC SSD device is the sequential write bandwidth (and IOPS)? In particular, there are some SD/MMC/CF cards for professional photography and

Hi, I''ve ordered a new server with: - 4x600GB Toshiba 10K SAS2 Disks - 2x100GB OCZ DENEVA 2R SYNC eMLC SATA (no expander so I hope no SAS/ SATA problems). Specs: http://www.oczenterprise.com/ssd-products/deneva-2-r-sata-6g-2.5-emlc.html I want to use the 2 OCZ SSDs as mirrored intent log devices, but as the intent log needs quite a small amount of the disks (10GB?), I was wondering

Greeting ALL I understand that L2ARC is still under enhancement. Does any one know if ZFS can be upgrades to include "Persistent L2ARC", ie. L2ARC will not loose its contents after system reboot ? -- Abdullah Al-Dahlawi George Washington University Department. Of Electrical & Computer Engineering ---- Check The Fastest 500 Super Computers Worldwide

I created a zfs pool with dedup with the following settings: zpool create data c8t1d0 zfs create data/shared zfs set dedup=on data/shared The thing I was wondering about was it seems like ZFS only dedup at the file level and not the block. When I make multiple copies of a file to the store I see an increase in the deup ratio, but when I copy similar files the ratio stays at 1.00x. -- This

Are there any drawbacks to partition a SSD in two parts and use L2ARC on one partition, and ZIL on the other? Any thoughts? -- This message posted from opensolaris.org

Hi, Out of pure curiosity, I was wondering, what would happen if one tries to use a regular 7200RPM (or 10K) drive as slog or L2ARC (or both)? I know these are designed with SSDs in mind, and I know it''s possible to use anything you want as cache. So would ZFS benefit from it? Would it be the same? Would it slow down? I guess it would slow things down, because it would be trying to

Hi. I can''t reach Brendan Gregg with this question (user unknown, he doesn''t work for Oracle anymore?), so I''m sending it here: FreeBSD users report much better performance and lower disk and CPU load when L2ARC also holds prefetched data (l2arc_noprefetch = B_FALSE). I was wondering what was the reason to avoid storing prefetched data on L2ARC vdevs by default. --

Yesterday morning I awoke to alerts from my SAN that one of my OS disks was faulty, FMA said it was in hardware failure. By the time I got to work (1.5 hours after the email) ALL of my pools were in a degraded state, and "tank" my primary pool had kicked in two hot spares because it was so discombobulated. ------------------- EMAIL ------------------- List of faulty resources:

Hello list, I''m having trouble with a server holding a lot of data. After a few months of uptime, it is currently rebooting from a lockup (reason unknown so far) but it is taking hours to boot up again. The boot process is stuck at the stage where it says: mounting zfs filesystems (1/5) the machine responds to pings and keystrokes. I can see disk activity; the disk leds blink one after

Hi, I don''t know if it''s already been discussed here, but while thinking about using the OCZ Vertex 2 Pro SSD (which according to spec page has supercaps built in) as a shared slog and L2ARC device it stroke me that this might not be a such a good idea. Because this SSD is MLC based, write cycles are an issue here, though I can''t find any number in their spec. Why do I