What is your parity check speed?

[gtroyp]

I was wondering, with new systems, faster SATA and faster drives what parity check speeds were like for other people. In order to gauge whether or not my system was running good bad or indifferent, I thought I would ask around.

 

For the record: my last parity check today, running 6.b6 on the system below,  Duration: 8 hours, 40 minutes, 1 second. Average speed: 96.2 MB/sec

[garycase]

Might be interesting data ... but quite frankly it's almost useless without also knowing the specifics of the system.    For example, if you built a nice new system with a bunch of 6TB WD Reds, but also had a couple of older, slower drives in it, those drives would limit the parity check speed, so it'd be FAR slower than if they weren't there.

 

[BRiT]

I call shenanigans on the 150+ MB/sec result.

[garycase]

I call shenanigans on the 150+ MB/sec result.

 

I'd be interested in seeing what an array using ONLY the new 1.2TB/platter 6TB WD Reds would do ... I would not be surprised to see them exceed that on the outer cylinders -- although they certainly wouldn't average that for the entire check.    The 1TB/platter WD Red Pro's (which run at 7200 rpm) should also have speeds above that on the outer cylinders.

 

... we're probably not far away (1-2 years) from having drives that can actually average that 

 

If a 22TB system has enough capacity for you, you could actually get FAR better than 150MB/s speeds ==>  just build a 22TB system using 24 of these:

http://www.newegg.com/Product/Product.aspx?Item=N82E16820147356

 

You would, of course, have to be a bit less price sensitive than the average UnRAID builder 

 

 

[garycase]

... and, as an afterthought ... think of the WRITE speeds you could get !!

 

[jumperalex]

91.9 MB/s  You can see my drive specs in my sig.

[BobPhoenix]

I voted 80-90 because the arrays I have collected data on are all off of sas expanders which from my testing has reduced my parity check speeds by 25%.  But it does allow me to get 24 drives off of a single IBM M1015 controller and save my PCIe slots for other cards.

[sgibbers17]

I call shenanigans on the 150+ MB/sec result.

 

I remember a build that someone used ssds.  That build should get those speeds.

[cassiusdrow]

Last Parity check on 08/01/2014 using 1,536k window, over a total of 2,930,266,532 blocks

Duration:  10:03:02 (36,182 secs).  Avg Speed: 79.09 MB/sec.

 

Specs in sig. 

[dmacias]

Duration: 11 hours, 59 minutes, 57 seconds. Average speed: 92.7 MB/sec

[garycase]

6 3TB WD Reds, Avg speed 111.87MB/s

 

[lionelhutz]

I have a 2 x Hitachi and 2 x Toshiba 3T drives on old hardware (AMD 740G chipset). The array is typically right around 150Mbps on a parity check. With the faster 3T+ drive sizes I actually expected more results in that speed range.

[archedraft]

Avg speed 88.23 MB/s (I have an older 1 TB WD I pulled from an enclosure that slows it down)

[garycase]

I have a 2 x Hitachi and 2 x Toshiba 3T drives on old hardware (AMD 740G chipset). The array is typically right around 150Mbps on a parity check. With the faster 3T+ drive sizes I actually expected more results in that speed range.

 

My system starts in that range, but doesn't average nearly that -- as I noted above the average is 111+ MB/s.    What is your system's average for the entire check?

 

I assume you're using 7200rpm drives, since there aren't any 1TB/platter drives shown in the platter capacity database for Hitachi drives (even the 6TB Helium unit uses 860GB platters).    This would give them sustained rates slightly faster than the WD Reds ... but they'd still slow down a good bit on the inner cylinders.

 

[lionelhutz]

What is your system's average for the entire check?

 

150Mbps is the average speed. I thought that was pretty clear in my last post.

 

[garycase]

What is your system's average for the entire check?

 

150Mbps is the average speed. I thought that was pretty clear in my last post.

 

So your parity checks only take 5 1/2 hours !!??

 

What are the model #'s for your drives?

 

[lionelhutz]

Yes, 5-1/2 hours to parity check with 3 x 3T data drives.

2 x TOSHIBA DT01ACA300

2 x Hitachi HDS723030BLE640

 

The Toshiba drives zero'd during the preclear at an average speed of 148Mbps.

[garycase]

That's definitely a very nice speed.    If you get that with 7200 rpm units with 860GB platters, it'd be very interesting to see what the new 1TB/platter 7200rpm WD Red Pro's will do.  In theory they should be 16% faster !!

 

[BRiT]

Yes, 5-1/2 hours to parity check with 3 x 3T data drives.

2 x TOSHIBA DT01ACA300

2 x Hitachi HDS723030BLE640

 

The Toshiba drives zero'd during the preclear at an average speed of 148Mbps.

 

Please post the syslog snippet for the parity check. Thanks.

[lionelhutz]

Yes, 5-1/2 hours to parity check with 3 x 3T data drives.

2 x TOSHIBA DT01ACA300

2 x Hitachi HDS723030BLE640

 

The Toshiba drives zero'd during the preclear at an average speed of 148Mbps.

 

Please post the syslog snippet for the parity check. Thanks.

 

Unfortunately I recently rebooted the server after the first of the month and I'm leaving to go away all weekend tonight. I could type a copy of any number I felt like anyways, so if you don't believe it I really don't care.

 

 

[garycase]

Yes, 5-1/2 hours to parity check with 3 x 3T data drives.

2 x TOSHIBA DT01ACA300

2 x Hitachi HDS723030BLE640

 

The Toshiba drives zero'd during the preclear at an average speed of 148Mbps.

 

That's an excellent average ... but easy to believe.  The Toshiba drives are 1TB/platter units, so these should be about 16% faster than the Hitachi's (which are only 860GB/platter units).

 

It's a bit surprising that the parity checks are actually faster than the pre-clears ... but that may simply be a function of the Pre-Clear code vs. UnRAID's parity check logic. 

 

 

[lionelhutz]

Had a power outage yesterday. I came home when the check was about 80% done and started accessing some TV episodes while the check finished.

 

Aug 20 22:24:40 MediaServer kernel: md: sync done. time=21101sec  =~ 5hrs, 52min or 142Mbps

 

 

[garycase]

As I noted earlier, that's easy to believe with all 7200rpm drives.  It'd be even faster if you didn't have the 860GB platter Hitachi's.

 

[dalben]

Last checked on Friday, 22-08-2014, 15:00 (today), finding 0 errors.

> Duration: 8 hours, 22 minutes, 47 seconds. Average speed: 132,6 MB/sec

[boxtor]

Parity: ST4000DM000 (4TB Seagate) drive

Data: 2x WDC_WD40EZRX (4TB WDC) drives

 

Last checked on Thu 28 Aug 2014 11:26:38 AM EDT EDT (today), finding 1 errors.

> Duration: 9 hours, 33 minutes, 22 seconds. Average speed: 116.3 MB/sec