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Where does my parity check speeds rank?

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I was wondering were my parity check speeds rank compared to some other users out there.. im not sure if my speeds are average or not.. Im seeing about 90MB/s for a 4tb parity drive with a 7 disk array. i know hardware has alot to do with it so here is a quick rundown of my setup..

 

Intel i7 5820k processor

Gigabyte x99p-SLI motherboard

64gb Gskill Ram

1 4tb seagate nas drive 6gb/s *parity drive*

2 4tb segate desktop 6gb/s

3 2tb seagate desktop 6gb/s    *2 on sata card*

1 2tb hitchi destop drive 3gb/s *on sata card*

1 1tb wd green drive 3gb/s.      *on sata card*

I have a sata card pcie 2.0x1 with 4 of the drives on it.

 

Any feedback will be appreciated.

Sorry if i posted this in the wrong place.

 

 

 

 

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I get 110 MB/s with a mix of newish 3TB and 6TB drives.  I'd call your speed decent, and within the expected range, but probably a little slower than full potential due to the older 1 and 2TB drives.  You're also close to maxing out the throughput of a PCIe 2.0 x1 card with 4 drives.  In theory that one lane card has 500 MB/s throughput but in practice you could be hitting limitations due to it as well.  Still, overall I'd say that you are within the expected range.

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Thanks for the reply. Do you think that if i upgrade my sata card to a SUPERMICRO AOC?SASLP?MV8 with the same older drives attached to it i would see a performance increase. I believe that card operates in a x8 slot.

 

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My guess is no, you wouldn't see an immediate increase.  If you want faster speeds I think you *would* have to upgrade the drives, and you *might* have to upgrade the card.  I'm not a fan of running 4 drives on an x1 card, but truthfully if you are running PCIe 2.0 or higher it should only be an issue with really fast hard drives or SSDs.

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The parity check speed is calculated by dividing the size of your parity disk by how long the parity check takes so it's not a real transfer rate, more of a guideline.

 

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I get 135 MB/s on a server with two parity disks and six data disks. The disks are all the same size and type: Toshiba MD04ACA500, 5 TB.

 

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Problem with this threads (and the posts within) is nobody is specifying whether or not these are the average speed as reported at the end, or a sample speed from looking at the Main tab 5 minutes into the check / rebuild.

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The figure I quoted is the average, as displayed by Dynamix and stored in the History.

 

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Im definitely guilty of looking at the speed within the first 5 mins but it seems to level out. Its taking me about 12 hours to complete the enitre parity check.. i just thought it would be a little faster than 12 hours. I was looking for the 6 or 7 hour range.

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Same, average as reported at the end.  As I have mixed disk sizes, 5 minutes in would represent the slowest sustained speed.

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Last checked on Wed 11 May 2016 05:39:02 AM MST (two days ago), finding 0 errors.

Duration: 18 hours, 53 minutes, 30 seconds. Average speed: 117.7 MB/sec

 

I've got mostly all 8TB & 4TB wd reds, dual parity. My smallest HDD is 4TB.

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Im definitely guilty of looking at the speed within the first 5 mins but it seems to level out. Its taking me about 12 hours to complete the enitre parity check.. i just thought it would be a little faster than 12 hours. I was looking for the 6 or 7 hour range.

6 to 7 hours isn't going to happen, for a 4TB parity drive that exceeds 180 MB/s.  The best consumer class hard drives available today max out in the 120 MB/s - 160 MB/s range.  You might be able to get close to that goal with enterprise class drives but that costs $$$$.

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Im definitely guilty of looking at the speed within the first 5 mins but it seems to level out. Its taking me about 12 hours to complete the enitre parity check.. i just thought it would be a little faster than 12 hours. I was looking for the 6 or 7 hour range.

 

You can improve it a lot by upgrading all the smaller disks to 4TB, would need to upgrade the pcie x1 controller also, still difficult to go below 8 hours with 4TB disks.

 

I consider anything above 100MB/s a good average speed.

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From what I've seen, the average parity check time for the average unRAID user is roughly 3 times the size of the parity drive, about 3 hours per terabyte.  That's based on average equipment and mixed drives, both in size and age.  That means about 12 hour parity checks for a 4TB parity drive.  Some users do get better than that, with all high performance drives on high performance controllers on high performance busses.  Users that talk about their parity check speeds often have higher performing hardware.  The average user however is likely to be reusing older hardware and drives, trying to extend their life (at least in the past before VM's).

 

If a user is getting less than 3 hours per terabyte, then there may be a problem with their hardware, or they are using somewhat lower performing hardware, such as very old drives, IDE busses, the PCI bus, etc.

 

My apologies to you speed merchants, but I didn't want average users feeling bad about their systems.

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I get around 170MB/s to start with, but by the end I am usually getting around 130-140MB/s.

 

I was actually wondering what speed to expect. So this is welcome information.

It takes me around 7 hours to Check and Correct 9 Tb.

 

 

One thing that bums me out about UnRaid is that it doesn't support SMB multichannel, (so my 4-port nic is useless, unless its passed through to a VM) So I can't transfer to my array at over gigabit speed (Without having expensive 10Gbit gear). I know that isn't an unraid thing though.

 

PS: Still very new to UnRaid, and the forums (as you can probably all tell).

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Well, the OP asked for some data points, specifically wanting to see how his own figures compare, so I don't feel that I'm bragging. I posted a good parity check speed (135 MB/s, average) because I'm using modern disks that are all the same capacity. They are 5 TB Toshibas that cost me around £100 each, which is somewhat less than the equivalent capacity Seagates, WDs and HGSTs.

 

The rest of my hardware is by no means high end. For the record it's an Asus A88XM-A motherboard, again fairly modern but by no means expensive, and a modest but effective A6-6400K APU. I have four disks (including the two parities) controlled by the motherboard and four controlled by an AOC-SASLP-MV8, which is now rather old but not over-stretched. I have more memory than I need (16 GiB), but it's cheap, so why not?

 

I run Plex, Krusader and MakeMKV as Dockers and I have a single simple Linux VM, with IOMMU switched off and no attempts at passing through hardware. So it's nothing like the dual Xeon set-ups with 10 Gb/s NICs I see several of the recent adopters of unRAID are using, and frankly, struggling with, going by their posts to the 6.2.0-beta threads. In fact, my most expensive single component is the power supply - a good investment, IMO. Overall, I'm very pleased to get respectable performance without a huge expenditure.

 

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One thing that bums me out about UnRaid is that it doesn't support SMB multichannel, (so my 4-port nic is useless, unless its passed through to a VM) So I can't transfer to my array at over gigabit speed (Without having expensive 10Gbit gear). I know that isn't an unraid thing though.

 

V6.2-beta21 uses samba 4.4 with experimental smb multichannel support, I can't get it to work for now but it should work in the near future.

 

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@loggers1234 I'm curious to know how (and why) you achieve 9 TB of parity?

 

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@loggers1234 I'm curious to know how (and why) you achieve 9 TB of parity?

Probably means 9TB total array size, based on the duration I'm guessing parity disk is 3TB.

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@loggers1234 I'm curious to know how (and why) you achieve 9 TB of parity?

Probably means 9TB total array size, based on the duration I'm guessing parity disk is 3TB.

 

Hmmm... His sig suggests otherwise...

 

Array: 4 x 3 Tb Western Digital Red

Parity: 9 TB

 

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Hmmm... His sig suggests otherwise...

 

Array: 4 x 3 Tb Western Digital Red

Parity: 9 TB

 

Didn't see the sig since they don't appear on tapatalk, but still believe my impression was right, some users confuse parity disk size with parity protected array size.

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On 5/14/2016 at 3:15 PM, RobJ said:

From what I've seen, the average parity check time for the average unRAID user is roughly 3 times the size of the parity drive, about 3 hours per terabyte.  That's based on average equipment and mixed drives, both in size and age.  That means about 12 hour parity checks for a 4TB parity drive.  Some users do get better than that, with all high performance drives on high performance controllers on high performance busses.  Users that talk about their parity check speeds often have higher performing hardware.  The average user however is likely to be reusing older hardware and drives, trying to extend their life (at least in the past before VM's).

 

If a user is getting less than 3 hours per terabyte, then there may be a problem with their hardware, or they are using somewhat lower performing hardware, such as very old drives, IDE busses, the PCI bus, etc.

 

My apologies to you speed merchants, but I didn't want average users feeling bad about their systems.

 

I am generally seeing 5 hours pr. TB, gues something is very wrong then :/

My Parity is 2x WDC_WD30EFRX
My 8 datadrives consists of a mix of WDC_WD30EFRX and WDC_WD20EARX

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Not sure what happened on Feb 11th.

 

Date Duration Speed Status
2018-08-19, 06:40:33 19 hr, 15 sec 117.0 MB/s OK
2018-08-08, 17:18:11 19 hr, 18 min, 10 sec 115.1 MB/s OK
2018-07-04, 18:51:46 20 hr, 51 min, 45 sec 106.5 MB/s OK
2018-05-02, 16:44:32 18 hr, 44 min, 31 sec 118.6 MB/s OK
2018-04-04, 15:59:54 17 hr, 59 min, 53 sec 123.5 MB/s OK
2018-03-07, 14:08:42 18 hr, 8 min, 41 sec 122.5 MB/s OK
2018-02-14, 10:41:58 18 hr, 33 min, 45 sec 119.7 MB/s OK
2018-02-11, 21:39:45 8 hr, 55 min, 14 sec 249.2 MB/s OK
2018-02-08, 09:19:49 17 hr, 19 min, 50 sec 128.3 MB/s OK
2018-01-03, 21:16:28 20 hr, 16 min, 27 sec 109.6 MB/s OK

 

 

 

 

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22 minutes ago, StevenD said:

Not sure what happened on Feb 11th.

 

Date Duration Speed Status
2018-08-19, 06:40:33 19 hr, 15 sec 117.0 MB/s OK
2018-08-08, 17:18:11 19 hr, 18 min, 10 sec 115.1 MB/s OK
2018-07-04, 18:51:46 20 hr, 51 min, 45 sec 106.5 MB/s OK
2018-05-02, 16:44:32 18 hr, 44 min, 31 sec 118.6 MB/s OK
2018-04-04, 15:59:54 17 hr, 59 min, 53 sec 123.5 MB/s OK
2018-03-07, 14:08:42 18 hr, 8 min, 41 sec 122.5 MB/s OK
2018-02-14, 10:41:58 18 hr, 33 min, 45 sec 119.7 MB/s OK
2018-02-11, 21:39:45 8 hr, 55 min, 14 sec 249.2 MB/s OK
2018-02-08, 09:19:49 17 hr, 19 min, 50 sec 128.3 MB/s OK
2018-01-03, 21:16:28 20 hr, 16 min, 27 sec 109.6 MB/s OK

 

Without further information, I would have to assume this is a faulty statistic, maybe a bug that was later fixed, and those numbers are actually for an incomplete parity check.

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There is a known "bug" when doing a data disk rebuild and the disk is smaller than the parity disk, it will calculate average speed based on the size of parity disk, which makes the result higher than the actual speed.

 

E.g. when your parity disk is 4TB and you rebuild a data disk of 2TB, the calculated speed is double the actual speed.

 

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