Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-29 Thread Ian Collins
On 08/ 4/12 09:50 PM, Eugen Leitl wrote: On Fri, Aug 03, 2012 at 08:39:55PM -0500, Bob Friesenhahn wrote: 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. Intel 311 with a good UPS would seem to be a

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-14 Thread Karl Rossing
On 08/06/2012 10:06 PM, Erik Trimble wrote: Honestly, I don't think this last point can be emphasized enough. SSDs of all flavors and manufacturers have a track record of *consistently* lying when returning from a cache flush command. There might exist somebody out there who actually does it

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-07 Thread Anonymous Remailer (austria)
It depends on the model. Consumer models are less likely to immediately flush. My understanding that this is done in part to do some write coalescing and reduce the number of P/E cycles. Enterprise models should either flush, or contain a super capacitor that provides enough power for the

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-07 Thread Sašo Kiselkov
On 08/07/2012 02:18 AM, Christopher George wrote: I mean this as constructive criticism, not as angry bickering. I totally respect you guys doing your own thing. Thanks, I'll try my best to address your comments... Thanks for your kind reply, though there are some points I'd like to address,

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-07 Thread Michael Hase
On Mon, 6 Aug 2012, Christopher George wrote: I mean this as constructive criticism, not as angry bickering. I totally respect you guys doing your own thing. Thanks, I'll try my best to address your comments... *) At least updated benchmarks your site to compare against modern

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-07 Thread Bob Friesenhahn
On Tue, 7 Aug 2012, Sašo Kiselkov wrote: MLC is so much cheaper that you can simply slap on twice as much and use the rest for ECC, mirroring or simply overprovisioning sectors. The common practice to extending the lifecycle of MLC is by short-stroking it, i.e. using only a fraction of the

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-07 Thread Sašo Kiselkov
On 08/07/2012 04:08 PM, Bob Friesenhahn wrote: On Tue, 7 Aug 2012, Sašo Kiselkov wrote: MLC is so much cheaper that you can simply slap on twice as much and use the rest for ECC, mirroring or simply overprovisioning sectors. The common practice to extending the lifecycle of MLC is by

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-07 Thread Christopher George
Very impressive iops numbers. Although I have some thoughts on the benchmarking method itself. Imho the comparison shouldn't be raw iops numbers on the ddrdrive itself as tested with iometer (it's only 4gb), The purpose of the benchmarks presented is to isolate the inherent capability of

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Matt Breitbach
Rossing Cc: ZFS filesystem discussion list Subject: 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

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Christopher George
Are people getting intel 330's for l2arc and 520's for slog? Unfortunately, the Intel 520 does *not* power protect it's on-board volatile cache (unlike the Intel 320/710 SSD). Intel has an eye-opening technology brief, describing the benefits of power-loss data protection at:

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Stefan Ring
Unfortunately, the Intel 520 does *not* power protect it's on-board volatile cache (unlike the Intel 320/710 SSD). Intel has an eye-opening technology brief, describing the benefits of power-loss data protection at:

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Brandon High
On Mon, Aug 6, 2012 at 2:15 PM, Stefan Ring stefan...@gmail.com wrote: So you're saying that SSDs don't generally flush data to stable medium when instructed to? So data written before an fsync is not guaranteed to be seen after a power-down? It depends on the model. Consumer models are less

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Bob Friesenhahn
On Mon, 6 Aug 2012, Christopher George wrote: Intel's brief also clears up a prior controversy of what types of data are actually cached, per the brief it's both user and system data! I am glad to hear that both user AND system data is stored. That is rather reassuring. :-) Is your

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Bob Friesenhahn
On Mon, 6 Aug 2012, Stefan Ring wrote: Intel's brief also clears up a prior controversy of what types of data are actually cached, per the brief it's both user and system data! So you're saying that SSDs don't generally flush data to stable medium when instructed to? So data written before an

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Christopher George
Is your DDRdrive product still supported and moving? Yes, we now exclusively target ZIL acceleration. We will be at the upcoming OpenStorage Summit 2012, and encourage those attending to stop by our booth and say hello :-) http://www.openstoragesummit.org/ Is it well supported for Illumos?

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Sašo Kiselkov
On 08/07/2012 12:12 AM, Christopher George wrote: Is your DDRdrive product still supported and moving? Yes, we now exclusively target ZIL acceleration. We will be at the upcoming OpenStorage Summit 2012, and encourage those attending to stop by our booth and say hello :-)

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Christopher George
I am glad to hear that both user AND system data is stored. That is rather reassuring. :-) I agree! --- [Excerpt from the linked Intel Technology Brief] What Type of Data is Protected: During an unsafe shutdown, firmware routines in the

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Christopher George
I mean this as constructive criticism, not as angry bickering. I totally respect you guys doing your own thing. Thanks, I'll try my best to address your comments... *) Increased capacity for high-volume applications. We do have a select number of customers striping two X1s for a total

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-06 Thread Erik Trimble
On 8/6/2012 2:53 PM, Bob Friesenhahn wrote: On Mon, 6 Aug 2012, Stefan Ring wrote: Intel's brief also clears up a prior controversy of what types of data are actually cached, per the brief it's both user and system data! So you're saying that SSDs don't generally flush data to stable medium

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-04 Thread Eugen Leitl
On Fri, Aug 03, 2012 at 08:39:55PM -0500, Bob Friesenhahn wrote: 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

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-04 Thread Hung-Sheng Tsao (LaoTsao) Ph.D
hi may be check out stec ssd or checkout the service manual of sun zfs appliance service manual to see the read and write ssd in the system regards Sent from my iPad On Aug 3, 2012, at 22:05, Hung-Sheng Tsao (LaoTsao) Ph.D laot...@gmail.com wrote: Intel 311 Series Larsen Creek 20GB 2.5

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-04 Thread Bob Friesenhahn
On Fri, 3 Aug 2012, Neil Perrin wrote: 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. -

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-03 Thread Bob Friesenhahn
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

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-03 Thread Hung-Sheng Tsao (LaoTsao) Ph.D
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 bfrie...@simple.dallas.tx.us wrote: On Fri, 3 Aug 2012, Karl Rossing wrote: I'm looking at

Re: [zfs-discuss] what have you been buying for slog and l2arc?

2012-08-03 Thread Neil Perrin
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,