similar to: Efficiency when reading the same file blocks

Would it be worthwhile to implement heuristics to auto-tune ''recordsize'', or would that not be worth the effort? -- Regards, Jeremy

Dear all, we''re currently looking forward to restructure our hardware environment for our datawarehousing product/suite/solution/whatever. We''re currently running the database side on various SF V440''s attached via dual FC to our SAN backend (EMC DMX3) with UFS. The storage system is (obviously in a SAN) shared between many systems. Performance is mediocre in terms

I was trying to simply test bandwidth that Solaris/ZFS (Nevada b63) can deliver from a drive, and doing this: dd if=(raw disk) of=/dev/null gives me around 80MB/s, while dd if=(file on ZFS) of=/dev/null gives me only 35MB/s!?. I am getting basically the same result whether it is single zfs drive, mirror or a stripe (I am testing with two Seagate 7200.10 320G drives hanging off the same interface

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 zpool and zfs report different free space because zfs takes into account an internal reservation of 32MB or 1/64 of the capacity of the pool, what is bigger. So in a 2TB Harddisk, the reservation would be 32 gigabytes. Seems a bit excessive to me... - -- Jesus Cea Avion _/_/ _/_/_/ _/_/_/ jcea at jcea.es -

It wouldn''t be proper to start my first post here without congratulations and thanks to the ZFS team for such an impressive piece of work. Anyway, on to my query. I''ve been trying out ZFS, with a particular focus in reducing latency in a specific application. This application has a fair amount of random writing going on in the background (which, of course, ZFS will make

Hello all, I understand that relatively high fragmentation is inherent to ZFS due to its COW and possible intermixing of metadata and data blocks (of which metadata path blocks are likely to expire and get freed relatively quickly). I believe it was sometimes implied on this list that such fragmentation for "static" data can be currently combatted only by zfs send-ing existing

Currently I''m trying to figure out the best zfs layout for a thumper wrt. to read AND write performance. I did some simple mkfile 512G tests and found out, that per average ~ 500 MB/s seems to be the maximum on can reach (tried initial default setup, all 46 HDDs as R0, etc.). According to http://www.amd.com/us-en/assets/content_type/DownloadableAssets/ArchitectureWP_062806.pdf I would

A) Resilver = Defrag. True/false? B) If I buy larger drives and resilver, does defrag happen? C) Does zfs send zfs receive mean it will defrag? -- This message posted from opensolaris.org

One thing I''ve been confused about for a long time is the relationship between ZFS, the ARC, and the page cache. We have an application that''s a quasi-database. It reads files by mmap()ing them. (writes are done via write()). We''re talking 100TB of data in files that are 100k->50G in size (the files have headers to tell the app what segment to map, so mapped chunks

Hi All ; One of our customer is suffered from FS being corrupted after an unattanded shutdonw due to power problem. They want to switch to ZFS. >From what I read on, ZFS will most probably not be corrupted from the same event. But I am not sure how will Oracle be affected from a sudden power outage when placed over ZFS ? Any comments ? PS: I am aware of UPS''s and

Hi All, We are currently in the process of testing Solaris 10 with ZFS and Oracle and are running it on a T2000. When checking performance statistics on the T2000, we notice that only one thread of the CPU appears to be doing any of the processing. Leaving all other threads seemingly idle. Are there any tuning parameters that need to be set or changed when running Oracle on T2000 using

Hello zfs-code, http://cvs.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/fs/zfs/vdev_cache.c 72 * All i/os smaller than zfs_vdev_cache_max will be turned into 73 * 1<<zfs_vdev_cache_bshift byte reads by the vdev_cache (aka software 74 * track buffer). At most zfs_vdev_cache_size bytes will be kept in each 75 * vdev''s vdev_cache. While it

Hi, I''m running SunOS Release 5.10 Version Generic_118855-36 64-bit and in [b]/etc/system[/b] I put: [b]set zfs:zfs_nocacheflush = 1[/b] And after rebooting, I get the message: [b]sorry, variable ''zfs_nocacheflush'' is not defined in the ''zfs'' module[/b] So is this variable not available in the Solaris kernel? I''m getting really poor

I had to let this go and get on with testing DB2 on Solaris. I had to abandon zfs on local discs in x64 Solaris 10 5/08. The situation was that: * DB2 buffer pools occupied up to 90% of 32GB RAM on each host * DB2 cached the entire database in its buffer pools o having the file system repeat this was not helpful * running high-load DB2 tests for 2 weeks showed 100%

HI, The question is a ZFS performance question in reguards to SAN traffic. We are trying to benchmark ZFS vx VxFS file systems and I get the following performance results. Test Setup: Solaris 10: 11/06 Dual port Qlogic HBA with SFCSM (for ZFS) and DMP (of VxFS) Sun Fire v490 server LSI Raid 3994 on backend ZFS Record Size: 128KB (default) VxFS Block Size: 8KB(default) The only thing

I''m new so opensolaris and very new to ZFS. In the past we have always used linux for our database backends. So now we are looking for a new database server to give us a big performance boost, and also the possibility for scalability. Our current database consists mainly of a huge table containing about 230 million records and a few (relatively) smaller tables (something like 13 million

Hi, There''s something really bizarre in ZFS snaphot specs : "Uses no separate backing store." . Hum...if I want to mutualize one physical volume somewhere in my SAN as THE snaphots backing-store...it becomes impossible to do ! Really bad. Is there any chance to have a "backing-store-file" option in a future release ? In the same idea, it would be great to

A customer has a zpool where their spectral analysis applications create a ton (millions?) of very small files that are typically 1858 bytes in length. They''re using ZFS because UFS consistently runs out of inodes. I''m assuming that ZFS aggregates these little files into recordsize (128K?) blobs for writes. This seems to go reasonably well amazingly enough. Reads are a

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

Hi All, Its been a while since I touched zfs. Is the below still the case with zfs and hardware raid array? Do we still need to provide two luns from the hardware raid then zfs mirror those two luns? http://www.opensolaris.org/os/community/zfs/faq/#hardwareraid Thanks, Shawn -- This message posted from opensolaris.org