Re: [zfs-discuss] what have you been buying for slog and l2arc?
On 08/03/12 19:39, Bob Friesenhahn wrote: On Fri, 3 Aug 2012, Karl Rossing wrote: I'm looking at http://www.intel.com/content/www/us/en/solid-state-drives/solid-state-drives-ssd.html wondering what I should get. Are people getting intel 330's for l2arc and 520's for slog? For the slog, you should look for a SLC technology SSD which saves unwritten data on power failure. In Intel-speak, this is called "Enhanced Power Loss Data Protection". I am not running across any Intel SSDs which claim to match these requirements. - That shouldn't be necessary. ZFS flushes the write cache for any device written before returning from the synchronous request to ensure data stability. Extreme write IOPS claims in consumer SSDs are normally based on large write caches which can lose even more data if there is a power failure. Bob ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] what have you been buying for slog and l2arc?
Intel 311 Series Larsen Creek 20GB 2.5" SATA II SLC Enterprise Solid State Disk SSDSA2VP020G201 Average Rating (12 reviews) Write a Review Sent from my iPad On Aug 3, 2012, at 21:39, Bob Friesenhahn wrote: > On Fri, 3 Aug 2012, Karl Rossing wrote: > >> I'm looking at >> http://www.intel.com/content/www/us/en/solid-state-drives/solid-state-drives-ssd.html >> wondering what I should get. >> >> Are people getting intel 330's for l2arc and 520's for slog? > > For the slog, you should look for a SLC technology SSD which saves unwritten > data on power failure. In Intel-speak, this is called "Enhanced Power Loss > Data Protection". I am not running across any Intel SSDs which claim to > match these requirements. > > Extreme write IOPS claims in consumer SSDs are normally based on large write > caches which can lose even more data if there is a power failure. > > 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 ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] what have you been buying for slog and l2arc?
On Fri, 3 Aug 2012, Karl Rossing wrote: I'm looking at http://www.intel.com/content/www/us/en/solid-state-drives/solid-state-drives-ssd.html wondering what I should get. Are people getting intel 330's for l2arc and 520's for slog? For the slog, you should look for a SLC technology SSD which saves unwritten data on power failure. In Intel-speak, this is called "Enhanced Power Loss Data Protection". I am not running across any Intel SSDs which claim to match these requirements. Extreme write IOPS claims in consumer SSDs are normally based on large write caches which can lose even more data if there is a power failure. 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] Missing disk space
You said you're new to ZFS so might consider using zpool list and zfs list rather df -k to reconcile your disk space. In addition, your pool type (mirrored on RAIDZ) provides a different space perspective in zpool list that is not always easy to understand. http://docs.oracle.com/cd/E23824_01/html/E24456/filesystem-6.html#scrolltoc See these sections: Displaying ZFS File System Information Resolving ZFS File System Space Reporting Issues Let us know if this doesn't help. Thanks, Cindy On 08/03/12 16:00, Burt Hailey wrote: I seem to be missing a large amount of disk space and am not sure how to locate it. My pool has a total of 1.9TB of disk space. When I run df -k I see that the pool is using ~650GB of space and has only ~120GB available. Running zfs list shows that my pool (localpool) is using 1.67T. When I total up the amount of snapshots I see that they are using <250GB. Unless I’m missing something it appears that there is ~750GB of disk space that is unaccounted for. We do hourly snapshots. Two days ago I deleted 100GB of data and did not see a corresponding increase in snapshot sizes. I’m new to zfs and am reading the zfs admin handbook but I wanted to post this to get some suggestions on what to look at. Burt Hailey ___ 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
[zfs-discuss] Missing disk space
I seem to be missing a large amount of disk space and am not sure how to locate it. My pool has a total of 1.9TB of disk space. When I run df -k I see that the pool is using ~650GB of space and has only ~120GB available. Running zfs list shows that my pool (localpool) is using 1.67T. When I total up the amount of snapshots I see that they are using <250GB. Unless I'm missing something it appears that there is ~750GB of disk space that is unaccounted for. We do hourly snapshots. Two days ago I deleted 100GB of data and did not see a corresponding increase in snapshot sizes. I'm new to zfs and am reading the zfs admin handbook but I wanted to post this to get some suggestions on what to look at. Burt Hailey ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] what have you been buying for slog and l2arc?
I'm looking at http://www.intel.com/content/www/us/en/solid-state-drives/solid-state-drives-ssd.html wondering what I should get. Are people getting intel 330's for l2arc and 520's for slog? Karl CONFIDENTIALITY NOTICE: This communication (including all attachments) is confidential and is intended for the use of the named addressee(s) only and may contain information that is private, confidential, privileged, and exempt from disclosure under law. All rights to privilege are expressly claimed and reserved and are not waived. Any use, dissemination, distribution, copying or disclosure of this message and any attachments, in whole or in part, by anyone other than the intended recipient(s) is strictly prohibited. If you have received this communication in error, please notify the sender immediately, delete this communication from all data storage devices and destroy all hard copies. ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Can the ZFS "copies" attribute substitute HW disk redundancy?
On Aug 2, 2012, at 5:40 PM, Nigel W wrote: > On Thu, Aug 2, 2012 at 3:39 PM, Richard Elling > wrote: >> On Aug 1, 2012, at 8:30 AM, Nigel W wrote: >> >> >> Yes. +1 >> >> The L2ARC as is it currently implemented is not terribly useful for >> storing the DDT in anyway because each DDT entry is 376 bytes but the >> L2ARC reference is 176 bytes, so best case you get just over double >> the DDT entries in the L2ARC as what you would get into the ARC but >> then you have also have no ARC left for anything else :(. >> >> >> You are making the assumption that each DDT table entry consumes one >> metadata update. This is not the case. The DDT is implemented as an AVL >> tree. As per other metadata in ZFS, the data is compressed. So you cannot >> make a direct correlation between the DDT entry size and the affect on the >> stored metadata on disk sectors. >> -- richard >> > It's compressed even when in the ARC? That is a slightly odd question. The ARC contains ZFS blocks. DDT metadata is manipulated in memory as an AVL tree, so what you can see in the ARC is the metadata blocks that were read and uncompressed from the pool or packaged in blocks and written to the pool. Perhaps it is easier to think of them as metadata in transition? :-) -- richard -- ZFS Performance and Training richard.ell...@richardelling.com +1-760-896-4422 ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] number of blocks changes
2012-08-03 17:18, Justin Stringfellow пишет: While this isn't causing me any problems, I'm curious as to why this is happening...: $ dd if=/dev/random of=ob bs=128k count=1 && while true do ls -s ob sleep 1 done 0+1 records in 0+1 records out 1 ob ... I was expecting the '1', since this is a zfs with recordsize=128k. Not sure I understand the '4', or why it happens ~30s later. Can anyone distribute clue in my direction? s10u10, running 144488-06 KU. zfs is v4, pool is v22. I think for the cleanness of the experiment, you should also include "sync" after the dd's, to actually commit your file to the pool. What is the pool's redundancy setting? I am not sure what "ls -s" actually accounts for file's FS-block usage, but I wonder if it might include metadata (relevant pieces of the block pointer tree individual to the file). Also check if the disk usage reported by "du -k ob" varies similarly, for the fun of it? //Jim ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] number of blocks changes
On 08/03/2012 03:18 PM, Justin Stringfellow wrote: > While this isn't causing me any problems, I'm curious as to why this is > happening...: > > > > $ dd if=/dev/random of=ob bs=128k count=1 && while true Can you check whether this happens from /dev/urandom as well? -- Saso ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] number of blocks changes
While this isn't causing me any problems, I'm curious as to why this is happening...: $ dd if=/dev/random of=ob bs=128k count=1 && while true > do > ls -s ob > sleep 1 > done 0+1 records in 0+1 records out 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 1 ob 4 ob < changes here 4 ob 4 ob ^C $ ls -l ob -rw-r--r-- 1 justin staff 1040 Aug 3 09:28 ob I was expecting the '1', since this is a zfs with recordsize=128k. Not sure I understand the '4', or why it happens ~30s later. Can anyone distribute clue in my direction? s10u10, running 144488-06 KU. zfs is v4, pool is v22. cheers, --justin -bash-3.00$ ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss