* Intel X25-M MLC SSD benchmarks @ 2008-12-10 21:15 ` Raz Ben-Yehuda 2008-12-10 21:39 ` Matthew Wilcox 2008-12-12 18:10 ` Greg Freemyer 0 siblings, 2 replies; 14+ messages in thread From: Raz Ben-Yehuda @ 2008-12-10 21:15 UTC (permalink / raw) To: linux-ide, linux-scsi Hello I am wondering if anyone tried Intel new disks. I benchmark them and I am a bit confused. According to the spec a single disk should provide 70MB/s write and 250 MB/s read. Reads are ok. I am reaching this number, but writes are bad. With writes I am getting 20MB/s. I am using a dd for the test, and a deadline-line scheduler. Thank you Raz ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-10 21:15 ` Intel X25-M MLC SSD benchmarks Raz Ben-Yehuda @ 2008-12-10 21:39 ` Matthew Wilcox 2008-12-10 22:12 ` Raz Ben-Yehuda 2008-12-12 18:10 ` Greg Freemyer 1 sibling, 1 reply; 14+ messages in thread From: Matthew Wilcox @ 2008-12-10 21:39 UTC (permalink / raw) To: Raz Ben-Yehuda; +Cc: linux-ide, linux-scsi On Wed, Dec 10, 2008 at 11:15:12PM +0200, Raz Ben-Yehuda wrote: > Hello > I am wondering if anyone tried Intel new disks. I benchmark them and I > am a bit confused. > According to the spec a single disk should provide 70MB/s write and 250 > MB/s read. Reads are ok. I am reaching this number, but writes are bad. > With writes I am getting 20MB/s. > I am using a dd for the test, and a deadline-line scheduler. What command exactly are you using, and have you tried using the no-op elevator instead of deadline? Also, what controller is it hooked up to? -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." ^ permalink raw reply [flat|nested] 14+ messages in thread
* RE: Intel X25-M MLC SSD benchmarks 2008-12-10 21:39 ` Matthew Wilcox @ 2008-12-10 22:12 ` Raz Ben-Yehuda 2008-12-11 3:44 ` Matthew Wilcox 2008-12-12 3:27 ` Eric D. Mudama 0 siblings, 2 replies; 14+ messages in thread From: Raz Ben-Yehuda @ 2008-12-10 22:12 UTC (permalink / raw) To: Matthew Wilcox; +Cc: linux-ide, linux-scsi -----Original Message----- From: linux-ide-owner@vger.kernel.org [mailto:linux-ide-owner@vger.kernel.org] On Behalf Of Matthew Wilcox Sent: Wednesday, December 10, 2008 11:40 PM To: Raz Ben-Yehuda Cc: linux-ide@vger.kernel.org; linux-scsi@vger.kernel.org Subject: Re: Intel X25-M MLC SSD benchmarks On Wed, Dec 10, 2008 at 11:15:12PM +0200, Raz Ben-Yehuda wrote: > Hello > I am wondering if anyone tried Intel new disks. I benchmark them and I > am a bit confused. > According to the spec a single disk should provide 70MB/s write and 250 > MB/s read. Reads are ok. I am reaching this number, but writes are bad. > With writes I am getting 20MB/s. > I am using a dd for the test, and a deadline-line scheduler. What command exactly are you using, and have you tried using the no-op elevator instead of deadline? Also, what controller is it hooked up to? I first thank you for your reply. I did not want to dive into details because it does not matter. Whether noop,deadline, deadline parameters... As for the controller I used 4 different controllers. Adaptec,AHCI and Intel as Integrated chips on the 1025W-UR supermicro motherboard, and a 4-th controller SuperMicro UIO Adaptec aac card. All gave same results for most dd writes commands. dd if=/dev/zero of=/dev/sda bs=1M count=1000 oflag=direct , and many other variants such erase block size ( 128K ) , several erase block size and so on. Kernel is 2.6.18-8.el5. I used all on a supermicro 1025W-UR. Disks have a SAS interface, 80GB. Also, I would like to note, I have 8 disks in array, while each one perform READS 250 MB/s, together I degrade to 200 MB/s each. As for writes I always reach 20 MB/s at best, from a single disk or 20x8 in array. A disk in /proc/scsi/scsi identifies like this: Host: scsi3 Channel: 00 Id: 00 Lun: 00 Vendor: ATA Model: INTEL SSDSA2MH08 Rev: 045C Type: Direct-Access ANSI SCSI revision: 05 And this is how my poor iostat looks: avg-cpu: %user %nice %system %iowait %steal %idle 0.00 0.00 0.13 24.78 0.00 75.09 Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn hda 0.00 0.00 0.00 0 0 sda 33.00 0.00 11136.00 0 11136 sdb 126.00 0.00 42624.00 0 42624 sdc 87.00 0.00 29568.00 0 29568 sdd 122.00 0.00 41728.00 0 41728 sde 121.00 0.00 41344.00 0 41344 sdf 121.00 0.00 41448.00 0 41448 sdg 109.00 0.00 36736.00 0 36736 sdh 48.00 0.00 49152.00 0 49152 and this is lspci: 00:00.0 Host bridge: Intel Corporation 5400 Chipset Memory Controller Hub (rev 20) 00:01.0 PCI bridge: Intel Corporation 5400 Chipset PCI Express Port 1 (rev 20) 00:03.0 PCI bridge: Intel Corporation 5400 Chipset PCI Express Port 3 (rev 20) 00:05.0 PCI bridge: Intel Corporation 5400 Chipset PCI Express Port 5 (rev 20) 00:07.0 PCI bridge: Intel Corporation 5400 Chipset PCI Express Port 7 (rev 20) 00:09.0 PCI bridge: Intel Corporation 5400 Chipset PCI Express Port 9 (rev 20) 00:0f.0 System peripheral: Intel Corporation 5400 Chipset QuickData Technology Device (rev 20) 00:10.0 Host bridge: Intel Corporation 5400 Chipset FSB Registers (rev 20) 00:10.1 Host bridge: Intel Corporation 5400 Chipset FSB Registers (rev 20) 00:10.2 Host bridge: Intel Corporation 5400 Chipset FSB Registers (rev 20) 00:10.3 Host bridge: Intel Corporation 5400 Chipset FSB Registers (rev 20) 00:10.4 Host bridge: Intel Corporation 5400 Chipset FSB Registers (rev 20) 00:11.0 Host bridge: Intel Corporation 5400 Chipset CE/SF Registers (rev 20) 00:15.0 Host bridge: Intel Corporation 5400 Chipset FBD Registers (rev 20) 00:15.1 Host bridge: Intel Corporation 5400 Chipset FBD Registers (rev 20) 00:16.0 Host bridge: Intel Corporation 5400 Chipset FBD Registers (rev 20) 00:16.1 Host bridge: Intel Corporation 5400 Chipset FBD Registers (rev 20) 00:1d.0 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #1 (rev 09) 00:1d.1 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #2 (rev 09) 00:1d.2 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #3 (rev 09) 00:1d.3 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #4 (rev 09) 00:1d.7 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset EHCI USB2 Controller (rev 09) 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev d9) 00:1f.0 ISA bridge: Intel Corporation 631xESB/632xESB/3100 Chipset LPC Interface Controller (rev 09) 00:1f.1 IDE interface: Intel Corporation 631xESB/632xESB IDE Controller (rev 09) 00:1f.2 RAID bus controller: Intel Corporation 631xESB/632xESB SATA RAID Controller (rev 09) 00:1f.3 SMBus: Intel Corporation 631xESB/632xESB/3100 Chipset SMBus Controller (rev 09) 01:00.0 Ethernet controller: Intel Corporation 82598EB 10 Gigabit AT CX4 Network Connection (rev 01) 01:00.1 Ethernet controller: Intel Corporation 82598EB 10 Gigabit AT CX4 Network Connection (rev 01) 02:00.0 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express Upstream Port (rev 01) 02:00.3 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express to PCI-X Bridge (rev 01) 03:00.0 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express Downstream Port E1 (rev 01) 06:00.0 RAID bus controller: Adaptec AAC-RAID (rev 09) 07:00.0 Ethernet controller: Intel Corporation 82598EB 10 Gigabit AT CX4 Network Connection (rev 01) 07:00.1 Ethernet controller: Intel Corporation 82598EB 10 Gigabit AT CX4 Network Connection (rev 01) 08:00.0 Ethernet controller: Intel Corporation 82575EB Gigabit Network Connection (rev 02) 08:00.1 Ethernet controller: Intel Corporation 82575EB Gigabit Network Connection (rev 02) 09:01.0 VGA compatible controller: ATI Technologies Inc ES1000 (rev 02) [ -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-10 22:12 ` Raz Ben-Yehuda @ 2008-12-11 3:44 ` Matthew Wilcox 2008-12-12 3:27 ` Eric D. Mudama 1 sibling, 0 replies; 14+ messages in thread From: Matthew Wilcox @ 2008-12-11 3:44 UTC (permalink / raw) To: Raz Ben-Yehuda; +Cc: linux-ide, linux-scsi On Thu, Dec 11, 2008 at 12:12:37AM +0200, Raz Ben-Yehuda wrote: > I did not want to dive into details because it does not matter. Whether > noop,deadline, deadline parameters... > As for the controller I used 4 different controllers. Adaptec,AHCI and > Intel as Integrated chips on the 1025W-UR supermicro motherboard, and a > 4-th controller SuperMicro UIO Adaptec aac card. > All gave same results for most dd writes commands. > dd if=/dev/zero of=/dev/sda bs=1M count=1000 oflag=direct , and many > other variants such erase block size ( 128K ) , several erase block size > and so on. Kernel is 2.6.18-8.el5. OK, I suspect you aren't giving the drive enough work to do for it to perform at its best. Try doing something like this: for i in $(seq 0 9); do \ dd if=/dev/zero of=/dev/sda bs=1M count=1000 oflag=direct \ seek=$(($i * 1000)) & \ done > I used all on a supermicro 1025W-UR. Disks have a SAS interface, 80GB. > Also, I would like to note, I have 8 disks in array, while each one > perform READS 250 MB/s, together I degrade to 200 MB/s each. As for That doesn't surprise me; you're probably hitting a limitation either of the array or the cable itself. A SAS cable can run up to 6Gbps, which will be around 600MB/s. So three drives should be able to saturate your SAS cable. If you're using an x4 link, that goes up to 2400MB/s which should be ample for 8 drives ... maybe you're using a 3Gbps cable which would limit each drive to 150MB/s. -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-10 22:12 ` Raz Ben-Yehuda 2008-12-11 3:44 ` Matthew Wilcox @ 2008-12-12 3:27 ` Eric D. Mudama 2008-12-12 4:55 ` Eric D. Mudama 2008-12-12 12:21 ` Raz Ben-Yehuda 1 sibling, 2 replies; 14+ messages in thread From: Eric D. Mudama @ 2008-12-12 3:27 UTC (permalink / raw) To: Raz Ben-Yehuda; +Cc: Matthew Wilcox, linux-ide, linux-scsi On 12/10/08, Raz Ben-Yehuda <razb@bitband.com> wrote: > All gave same results for most dd writes commands. > dd if=/dev/zero of=/dev/sda bs=1M count=1000 oflag=direct , and many > other variants such erase block size ( 128K ) , several erase block size > and so on. Kernel is 2.6.18-8.el5. > I used all on a supermicro 1025W-UR. Disks have a SAS interface, 80GB. > Also, I would like to note, I have 8 disks in array, while each one > perform READS 250 MB/s, together I degrade to 200 MB/s each. As for > writes I always reach 20 MB/s at best, from a single disk or 20x8 in > array. Out of curiosity, is write cache enabled or disabled on these devices? ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-12 3:27 ` Eric D. Mudama @ 2008-12-12 4:55 ` Eric D. Mudama 2008-12-12 7:15 ` Bart Van Assche 2008-12-12 12:15 ` Matthew Wilcox 2008-12-12 12:21 ` Raz Ben-Yehuda 1 sibling, 2 replies; 14+ messages in thread From: Eric D. Mudama @ 2008-12-12 4:55 UTC (permalink / raw) To: Raz Ben-Yehuda; +Cc: Matthew Wilcox, linux-ide, linux-scsi On 12/11/08, Eric D. Mudama <edmudama@gmail.com> wrote: > Out of curiosity, is write cache enabled or disabled on these devices? Oops, I just noticed the oflag=direct, that can have a huge performance difference depending on the block size. What numbers are you getting without oflag=direct? ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-12 4:55 ` Eric D. Mudama @ 2008-12-12 7:15 ` Bart Van Assche 2008-12-12 14:25 ` Eric D. Mudama 2008-12-12 12:15 ` Matthew Wilcox 1 sibling, 1 reply; 14+ messages in thread From: Bart Van Assche @ 2008-12-12 7:15 UTC (permalink / raw) To: Eric D. Mudama; +Cc: Raz Ben-Yehuda, Matthew Wilcox, linux-ide, linux-scsi On Fri, Dec 12, 2008 at 5:55 AM, Eric D. Mudama <edmudama@gmail.com> wrote: > On 12/11/08, Eric D. Mudama <edmudama@gmail.com> wrote: >> Out of curiosity, is write cache enabled or disabled on these devices? > > Oops, I just noticed the oflag=direct, that can have a huge > performance difference depending on the block size. > > What numbers are you getting without oflag=direct? IMHO repeating the measurements without oflag=direct does not make sense: measurements with oflag=direct tell something about the performance of the SSD and the software layers on top of it. Without oflag=direct writes are buffered by Linux and data is written asynchronously to the SSD. Bart. ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-12 7:15 ` Bart Van Assche @ 2008-12-12 14:25 ` Eric D. Mudama 2008-12-12 15:20 ` Matthew Wilcox 0 siblings, 1 reply; 14+ messages in thread From: Eric D. Mudama @ 2008-12-12 14:25 UTC (permalink / raw) To: Bart Van Assche; +Cc: Raz Ben-Yehuda, Matthew Wilcox, linux-ide, linux-scsi On Fri, Dec 12, 2008 at 12:15 AM, Bart Van Assche <bart.vanassche@gmail.com> wrote: > > On Fri, Dec 12, 2008 at 5:55 AM, Eric D. Mudama <edmudama@gmail.com> wrote: > > On 12/11/08, Eric D. Mudama <edmudama@gmail.com> wrote: > >> Out of curiosity, is write cache enabled or disabled on these devices? > > > > Oops, I just noticed the oflag=direct, that can have a huge > > performance difference depending on the block size. > > > > What numbers are you getting without oflag=direct? > > IMHO repeating the measurements without oflag=direct does not make > sense: measurements with oflag=direct tell something about the > performance of the SSD and the software layers on top of it. Without > oflag=direct writes are buffered by Linux and data is written > asynchronously to the SSD. Oops, I guess I assumed that by writing a few gigabytes of data it wouldn't matter that much. I'll run the test again in a bit once I'm off this solaris machine. ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-12 14:25 ` Eric D. Mudama @ 2008-12-12 15:20 ` Matthew Wilcox 2008-12-12 15:55 ` Eric D. Mudama 0 siblings, 1 reply; 14+ messages in thread From: Matthew Wilcox @ 2008-12-12 15:20 UTC (permalink / raw) To: Eric D. Mudama; +Cc: Bart Van Assche, Raz Ben-Yehuda, linux-ide, linux-scsi On Fri, Dec 12, 2008 at 07:25:18AM -0700, Eric D. Mudama wrote: > Oops, I guess I assumed that by writing a few gigabytes of data it > wouldn't matter that much. I'll run the test again in a bit once I'm > off this solaris machine. You need to rescale for 2008; people often have 4GB or more RAM in their machines ... hell, I have one machine here from 2002 with 14GB in it (I don't power it up very often because it's too noisy). The test was only writing 1GB of data, which would fit in the page cache of my laptop, never mind the kind of machine that's likely to have an 8-way array attached to it. -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-12 15:20 ` Matthew Wilcox @ 2008-12-12 15:55 ` Eric D. Mudama 2008-12-12 17:12 ` Raz Ben-Yehuda 0 siblings, 1 reply; 14+ messages in thread From: Eric D. Mudama @ 2008-12-12 15:55 UTC (permalink / raw) To: Matthew Wilcox; +Cc: Bart Van Assche, Raz Ben-Yehuda, linux-ide, linux-scsi On 12/12/08, Matthew Wilcox <matthew@wil.cx> wrote: > On Fri, Dec 12, 2008 at 07:25:18AM -0700, Eric D. Mudama wrote: >> Oops, I guess I assumed that by writing a few gigabytes of data it >> wouldn't matter that much. I'll run the test again in a bit once I'm >> off this solaris machine. > > You need to rescale for 2008; people often have 4GB or more RAM in their > machines ... hell, I have one machine here from 2002 with 14GB in it > (I don't power it up very often because it's too noisy). The test was > only writing 1GB of data, which would fit in the page cache of my laptop, > never mind the kind of machine that's likely to have an 8-way array > attached to it. I just retested on a linux box at work, and got 79 MB/s on both the X18-M and X25-M, and 197MB/s on an X25-E. All were done with bs=1M count=1000 oflag=direct. --eric ^ permalink raw reply [flat|nested] 14+ messages in thread
* RE: Intel X25-M MLC SSD benchmarks 2008-12-12 15:55 ` Eric D. Mudama @ 2008-12-12 17:12 ` Raz Ben-Yehuda 0 siblings, 0 replies; 14+ messages in thread From: Raz Ben-Yehuda @ 2008-12-12 17:12 UTC (permalink / raw) To: Eric D. Mudama; +Cc: linux-ide, linux-scsi -----Original Message----- From: Eric D. Mudama [mailto:edmudama@gmail.com] Sent: Friday, December 12, 2008 5:55 PM To: Matthew Wilcox Cc: Bart Van Assche; Raz Ben-Yehuda; linux-ide@vger.kernel.org; linux-scsi@vger.kernel.org Subject: Re: Intel X25-M MLC SSD benchmarks On 12/12/08, Matthew Wilcox <matthew@wil.cx> wrote: > On Fri, Dec 12, 2008 at 07:25:18AM -0700, Eric D. Mudama wrote: >> Oops, I guess I assumed that by writing a few gigabytes of data it >> wouldn't matter that much. I'll run the test again in a bit once I'm >> off this solaris machine. > > You need to rescale for 2008; people often have 4GB or more RAM in their > machines ... hell, I have one machine here from 2002 with 14GB in it > (I don't power it up very often because it's too noisy). The test was > only writing 1GB of data, which would fit in the page cache of my laptop, > never mind the kind of machine that's likely to have an 8-way array > attached to it. >>I just retested on a linux box at work, and got 79 MB/s on both the >>X18-M and X25-M, and 197MB/s on an X25-E. All were done with bs=1M >>count=1000 oflag=direct. What is the serial number of your x25.M ? what controller ? How new is it ? Please dd all disk and then retest, just to be sure you used all erase blocks. --<<eric ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-12 4:55 ` Eric D. Mudama 2008-12-12 7:15 ` Bart Van Assche @ 2008-12-12 12:15 ` Matthew Wilcox 1 sibling, 0 replies; 14+ messages in thread From: Matthew Wilcox @ 2008-12-12 12:15 UTC (permalink / raw) To: Eric D. Mudama; +Cc: Raz Ben-Yehuda, linux-ide, linux-scsi On Thu, Dec 11, 2008 at 09:55:56PM -0700, Eric D. Mudama wrote: > On 12/11/08, Eric D. Mudama <edmudama@gmail.com> wrote: > > Out of curiosity, is write cache enabled or disabled on these devices? > > Oops, I just noticed the oflag=direct, that can have a huge > performance difference depending on the block size. > > What numbers are you getting without oflag=direct? Without the oflag=direct option, you're measuring the performance of the Linux page cache. That's not very interesting. -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." ^ permalink raw reply [flat|nested] 14+ messages in thread
* RE: Intel X25-M MLC SSD benchmarks 2008-12-12 3:27 ` Eric D. Mudama 2008-12-12 4:55 ` Eric D. Mudama @ 2008-12-12 12:21 ` Raz Ben-Yehuda 1 sibling, 0 replies; 14+ messages in thread From: Raz Ben-Yehuda @ 2008-12-12 12:21 UTC (permalink / raw) To: Eric D. Mudama; +Cc: linux-ide, linux-scsi -----Original Message----- From: Eric D. Mudama [mailto:edmudama@gmail.com] Sent: Friday, December 12, 2008 5:28 AM To: Raz Ben-Yehuda Cc: Matthew Wilcox; linux-ide@vger.kernel.org; linux-scsi@vger.kernel.org Subject: Re: Intel X25-M MLC SSD benchmarks On 12/10/08, Raz Ben-Yehuda <razb@bitband.com> wrote: > All gave same results for most dd writes commands. > dd if=/dev/zero of=/dev/sda bs=1M count=1000 oflag=direct , and many > other variants such erase block size ( 128K ) , several erase block size > and so on. Kernel is 2.6.18-8.el5. > I used all on a supermicro 1025W-UR. Disks have a SAS interface, 80GB. > Also, I would like to note, I have 8 disks in array, while each one > perform READS 250 MB/s, together I degrade to 200 MB/s each. As for > writes I always reach 20 MB/s at best, from a single disk or 20x8 in > array. >>Out of curiosity, is write cache enabled or disabled on these devices? Does not matter. In both cases same low numbers. Write cache depends on the controller defaults ( Adpaptec AHCI, Intel provides different default). ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: Intel X25-M MLC SSD benchmarks 2008-12-10 21:15 ` Intel X25-M MLC SSD benchmarks Raz Ben-Yehuda 2008-12-10 21:39 ` Matthew Wilcox @ 2008-12-12 18:10 ` Greg Freemyer 1 sibling, 0 replies; 14+ messages in thread From: Greg Freemyer @ 2008-12-12 18:10 UTC (permalink / raw) To: Raz Ben-Yehuda; +Cc: linux-ide, linux-scsi On Wed, Dec 10, 2008 at 4:15 PM, Raz Ben-Yehuda <razb@bitband.com> wrote: > Hello > I am wondering if anyone tried Intel new disks. I benchmark them and I > am a bit confused. > According to the spec a single disk should provide 70MB/s write and 250 > MB/s read. Reads are ok. I am reaching this number, but writes are bad. > With writes I am getting 20MB/s. > I am using a dd for the test, and a deadline-line scheduler. > > Thank you > Raz FYI: Some recent kernel's have performance bugs in /dev/zero. (The bug may only exist ins SuSE kernels, not sure.) Be sure to baseline it before you trust it for any benchmarks. My current machine/kernel is plenty fast to use but you need to be sure and it only takes a minute. # dd if=/dev/zero of=/dev/null bs=1M count=100000 100000+0 records in 100000+0 records out 104857600000 bytes (105 GB) copied, 33.4257 s, 3.1 GB/s Greg -- Greg Freemyer Litigation Triage Solutions Specialist http://www.linkedin.com/in/gregfreemyer First 99 Days Litigation White Paper - http://www.norcrossgroup.com/forms/whitepapers/99%20Days%20whitepaper.pdf The Norcross Group The Intersection of Evidence & Technology http://www.norcrossgroup.com ^ permalink raw reply [flat|nested] 14+ messages in thread
end of thread, other threads:[~2008-12-12 18:10 UTC | newest] Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- [not found] <AclbDGOLOskD7sbdTh+kIygApfPXZg==> 2008-12-10 21:15 ` Intel X25-M MLC SSD benchmarks Raz Ben-Yehuda 2008-12-10 21:39 ` Matthew Wilcox 2008-12-10 22:12 ` Raz Ben-Yehuda 2008-12-11 3:44 ` Matthew Wilcox 2008-12-12 3:27 ` Eric D. Mudama 2008-12-12 4:55 ` Eric D. Mudama 2008-12-12 7:15 ` Bart Van Assche 2008-12-12 14:25 ` Eric D. Mudama 2008-12-12 15:20 ` Matthew Wilcox 2008-12-12 15:55 ` Eric D. Mudama 2008-12-12 17:12 ` Raz Ben-Yehuda 2008-12-12 12:15 ` Matthew Wilcox 2008-12-12 12:21 ` Raz Ben-Yehuda 2008-12-12 18:10 ` Greg Freemyer
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.