similar to: ZFS ARC Cache and Solaris u8

Under Solaris 10 on a 4 core Sun Ultra 40 with 20GB RAM, I am setting up a Sun StorageTek 2540 with 12 300GB 15K RPM SAS drives and connected via load-shared 4Gbit FC links. This week I have tried many different configurations, using firmware managed RAID, ZFS managed RAID, and with the controller cache enabled or disabled. My objective is to obtain the best single-file write performance.

http://hardware.slashdot.org/story/09/06/09/2336223/Apple-Removes-Nearly-All-Reference-To-ZFS

If there were a ?zfs send? datastream saved someplace, is there a way to verify the integrity of that datastream without doing a ?zfs receive? and occupying all that disk space? I am aware that ?zfs send? is not a backup solution, due to vulnerability of even a single bit error, and lack of granularity, and other reasons. However ... There is an attraction to ?zfs send? as an augmentation to the

Interesting flash technology overview and SSD review here: http://www.anandtech.com/cpuchipsets/intel/showdoc.aspx?i=3403 and another review here: http://www.tomshardware.com/reviews/Intel-x25-m-SSD,2012.html Regards, -- Al Hopper Logical Approach Inc,Plano,TX al at logical-approach.com Voice: 972.379.2133 Timezone: US CDT OpenSolaris Governing Board (OGB) Member - Apr 2005

I''ve got a server that freezes when I run a zpool scrub from cron. Zpool scrub runs fine from the command line, no errors. The freeze happens within 30 seconds of the zpool scrub happening. The one core dump I succeeded in taking showed an arccache eating up all the ram. The server''s running Solaris 10 u3, kernel patch 127727-11 but it''s been patched and seems to have

Hi all Is it possible to securely delete a file from a zfs dataset/zpool once it''s been snapshotted, meaning "delete (and perhaps overwrite) all copies of this file"? Best regards roy -- Roy Sigurd Karlsbakk (+47) 97542685 roy at karlsbakk.net http://blogg.karlsbakk.net/ -- I all pedagogikk er det essensielt at pensum presenteres intelligibelt. Det er et element?rt imperativ

Today I updated the firmware on my StorageTek 2540 to the latest recommended version and am seeing radically difference performance when testing with iozone than I did in February of 2008. I am using Solaris 10 U5 with all the latest patches. This is the performance achieved (on a 32GB file) in February last year: KB reclen write rewrite read reread 33554432

I encountered an issue that people using OS-X systems as NFS clients need to be aware of. While not strictly a ZFS issue, it may be encounted most often by ZFS users since ZFS makes it easy to support and export per-user filesystems. The problem I encountered was when using ZFS to create exported per-user filesystems and the OS-X automounter to perform the necessary mount magic. OS-X

Hello all... I''m seeing this behaviour in an old build (89), and i just want to hear from you if there is some known bug about it. I''m aware of the "picket fencing" problem, and that ZFS is not choosing right if write to slog is better or not (thinking if we have a better throughput from disks). But i did not find anything about 100% slog activity (~115MB/s) blocks

My understanding is that if I "zfs set checksum=<different>" to change the algorithm that this will change the checksum algorithm for all FUTURE data blocks written, but does not in any way change the checksum for previously written data blocks. I need to corroborate this understanding. Could someone please point me to a document that states this? I have searched and searched

Hello, We have a new Thor here with 24TB of disk in (first of many, hopefully). We are trying to determine the bext practices with respect to file system management and sizing. Previously, we have tried to keep each file system to a max size of 500GB to make sure we could fit it all on a single tape, and to minimise restore times and impact should we experience some kind of volume

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

I have a Solaris 10 U5 system massively patched so that it supports ZFS pool version 15 (similar to U8, kernel Generic_141445-09), live upgrade components have been updated to Solaris 10 U8 versions from the DVD, and GRUB has been updated to support redundant menus across the UFS boot environments. I have studied the Solaris 10 Live Upgrade manual (821-0438) and am unable to find any

Hi, I just installed 2009.06 and found that compression isn''t enabled by default when filesystems are created. Does is make sense to have an RFE open for this? (I''ll open one tonight if need be.) We keep telling people to turn on compression. Are there any situations where turning on compression doesn''t make sense, like rpool/swap? what about rpool/dump? Thanks, ~~sa

I currently have a 7x1.5tb raidz1. I want to add "phase 2" which is another 7x1.5tb raidz1 Can I add the second phase to the first phase and basically have two raid5''s striped (in raid terms?) Yes, I probably should upgrade the zpool format too. Currently running snv_104. Also should upgrade to 110. If that is possible, would anyone happen to have the simple command lines to

Hi, Please forgive me if my searching-fu has failed me in this case, but I''ve been unable to find any information on how people are going about monitoring and alerting regarding memory usage on Solaris hosts using ZFS. The problem is not that the ZFS ARC is using up the memory, but that the script Nagios is using to check memory usage simply sees, say 96% RAM used, and alerts. The

Hi list, as this matter pops up every now and then in posts on this list I just want to clarify that the real performance of RaidZ (in its current implementation) is NOT anything that follows from raidz-style data efficient redundancy or the copy-on-write design used in ZFS. In a M-Way mirrored setup of N disks you get the write performance of the worst disk and a read performance that is

Hi All, I am looking at ZFS and I get that they call it RAIDZ which is similar to RAID 5, but what about RAID 10? Isn''t a RAID 10 setup better for data protection? So if I have 8 x 1.5tb drives, wouldn''t I: - mirror drive 1 and 5 - mirror drive 2 and 6 - mirror drive 3 and 7 - mirror drive 4 and 8 Then stripe 1,2,3,4 Then stripe 5,6,7,8 How does one do this with ZFS?

[Cross-posting to ldoms-discuss] We are occasionally seeing massive time-to-completions for I/O requests on ZFS file systems on a Sun T5220 attached to a Sun StorageTek 2540 and a Sun J4200, and using a SSD drive as a ZIL device. Primary access to this system is via NFS, and with NFS COMMITs blocking until the request has been sent to disk, performance has been deplorable. The NFS server is a

I''m looking for a way to backup my entire system, the rpool zfs pool to an external HDD so that it can be recovered in full if the internal HDD fails. Previously with Solaris 10 using UFS I would use ufsdump and ufsrestore, which worked so well, I was very confident with it. Now ZFS doesn''t have an exact replacement of this so I need to find a best practice to replace it.