Re: v-slow raid resync

I failed the suspect disk out of the array and now the rebuild is
16000K/sec 4x faster.

Strange.

Time to do some disk testing...

On 19 March 2014 14:59, Jeff Allison <[email protected]> wrote:
> I ran hdparm...
>
> [root@nas ~]# hdparm -tT /dev/sdd <-- dud disk
>
> /dev/sdd:
>  Timing cached reads:   2318 MB in  2.00 seconds = 1158.86 MB/sec
>  Timing buffered disk reads:   2 MB in 25.35 seconds =  80.79 kB/sec
>
> [root@nas ~]# hdparm -tT /dev/sdc <-- good disk
>
> /dev/sdc:
>  Timing cached reads:   2470 MB in  2.00 seconds = 1234.85 MB/sec
>  Timing buffered disk reads: 296 MB in  3.01 seconds =  98.35 MB/sec
>
> Not much in it.
>
> On 19 March 2014 14:23, Jeff Allison <[email protected]> wrote:
>> The disk sector sizes are the same on all the disks.
>>
>> Logical  Sector size:                   512 bytes
>> Physical Sector size:                  4096 bytes
>>
>> Is chunk size stripe size?
>>
>> [root@nas ~]# mdadm --detail /dev/md0
>> /dev/md0:
>>         Version : 1.2
>>   Creation Time : Fri Feb 21 09:33:55 2014
>>      Raid Level : raid5
>>      Array Size : 3905985536 (3725.04 GiB 3999.73 GB)
>>   Used Dev Size : 1952992768 (1862.52 GiB 1999.86 GB)
>>    Raid Devices : 4
>>   Total Devices : 4
>>     Persistence : Superblock is persistent
>>
>>     Update Time : Wed Mar 19 14:22:35 2014
>>           State : clean, reshaping
>>  Active Devices : 4
>> Working Devices : 4
>>  Failed Devices : 0
>>   Spare Devices : 0
>>
>>          Layout : left-symmetric
>>      Chunk Size : 512K
>>
>>  Reshape Status : 28% complete
>>   Delta Devices : 1, (3->4)
>>
>>            Name : nas.allygray.2y.net:0  (local to host nas.allygray.2y.net)
>>            UUID : 1a122cbe:ada65085:680e451c:180c7689
>>          Events : 21723
>>
>>     Number   Major   Minor   RaidDevice State
>>        0       8       17        0      active sync   /dev/sdb1
>>        1       8       33        1      active sync   /dev/sdc1
>>        3       8        1        2      active sync   /dev/sda1
>>        4       8       49        3      active sync   /dev/sdd1
>>
>> When I created the partitions I used the -a optimal which I thought sorted that?
>>
>> On 19 March 2014 14:11, Jake Anderson <[email protected]> wrote:
>>> its probably *madly* seeking which is why its so slow.
>>> I wonder, what is the block size you are using on the disk and the stripe
>>> size of your array?
>>>
>>> If you are read modify writing a 4K disk in 512k blocks it'll be dog slow.
>>>
>>> On 19/03/14 14:00, Jeff Allison wrote:
>>>>
>>>> The thing I find strange is that in iostat the disk shows as 100% at 3/4
>>>> MB/s.
>>>>
>>>> I wonder how iostat decides on the percent?
>>>>
>>>> On 19 March 2014 10:53, Jake Anderson <[email protected]> wrote:
>>>>>
>>>>> This isn't going to be an issue with sata vs whatever (though I do
>>>>> suggest
>>>>> running in ahci mode if thats an option)
>>>>>
>>>>> The issue is probably going to be how mdadm is growing the array, it will
>>>>> need to do a buttload of disk access to do that reading and writing every
>>>>> sector on every disk and trying to keep everything in a consistent state
>>>>> while doing so.
>>>>>
>>>>> I don't know if it applies to whatever raid level you are using but is
>>>>> there
>>>>> something like an --assume-clean option you can pass it?
>>>>> I'd also suggest asking in the mdadm list or perhaps IRC.
>>>>> http://forums.whirlpool.net.au/archive/1056831 might be of interest.
>>>>>
>>>>>
>>>>> On 18/03/14 20:02, Rachel Polanskis wrote:
>>>>>>
>>>>>> On 18 Mar 2014, at 6:46 pm, Jeff Allison <[email protected]>
>>>>>> wrote:
>>>>>>
>>>>>> That's installed unfortunately didn't fix my problem. How badly
>>>>>> configured
>>>>>> does a disk need to be to only run at 4mb
>>>>>>
>>>>>>
>>>>>>
>>>>>> Sorry for the suck eggs question, but you did enable all the features in
>>>>>> the BIOS e.g. turning on SATA II 3gbps support,
>>>>>> write cache disable etc?   In the URL link to the forum below they
>>>>>> discuss
>>>>>> all the optimum settings.  I am using
>>>>>> WD RED NAS drives (2x2tb) and Seagate 3Tb drives (latest model) in my
>>>>>> system so similar to yours....
>>>>>>
>>>>>> rachel
>>>>>>
>>>>>>
>>>>>>
>>>>>> On 18/03/2014 3:43 PM, "Rachel Polanskis" <[email protected]> wrote:
>>>>>> On 18 Mar 2014, at 3:14 pm, Jeff Allison <[email protected]>
>>>>>> wrote:
>>>>>>
>>>>>> Is it the O41072911.ROM?
>>>>>>
>>>>>> Did you use flashrom of the dos disk thingo.
>>>>>>
>>>>>> On 18 March 2014 14:06, gr0ve <[email protected]> wrote:
>>>>>>>
>>>>>>> Seriously, you should flash the BIOS!  I get 80mbps reads on ZFS
>>>>>>> and depending, 30-40mbps on writes.  Without the BIOS mod, you
>>>>>>> are getting only IDE speeds there.  The original BIOS holds this
>>>>>>> machine
>>>>>>> back and it is perfectly safe.  The BIOS ensures AHCI support is
>>>>>>> operational
>>>>>>> as well as the 3gbps SATA II bus. Once you see the improvement, you
>>>>>>> can choose to also select write cache enabled|disabled although
>>>>>>> this is best with a UPS ;)
>>>>>>>
>>>>>>>
>>>>>>> rachel
>>>>>>
>>>>>> Hi,
>>>>>> The HP BIOS version is the O41072911.ROM as you suggest.
>>>>>> You need this to install the "theBay" ROM as well.
>>>>>>
>>>>>> The process is shown online, but in short you copy the HP BIOS using a
>>>>>> DOS/windows installer to a USB stick then copy the "theBay" rom image
>>>>>> over
>>>>>> the
>>>>>> top. You could try to "dd" the image but it does some weird trickery to
>>>>>> make
>>>>>> the stick bootable for installing the BIOS.
>>>>>>
>>>>>> You can look for TheBay_Microserver_Bios_041.rar online.
>>>>>> The source information is:
>>>>>>
>>>>>>
>>>>>>
>>>>>> http://www.avforums.com/threads/hp-n36l-n40l-n54l-microserver-updated-ahci-bios-support.1521657/
>>>>>>
>>>>>> And it has all the guff on getting the BIOS onto your N54L and also tips
>>>>>> on how to configure it.
>>>>>> I have all the files if you need them....
>>>>>>
>>>>>> Once again, these are terrific little servers.  It has an internal USB
>>>>>> port so I just loaded FreeNAS
>>>>>> onto an 8Gb USB stick and boot from there.  All the internal SATA disks
>>>>>> are in ZFS disk pools which
>>>>>> do my bidding. As I use ZFS, I went with 8gb ECC memory. I also added an
>>>>>> additional Gigabit Ethernet adaptor as the built in broadcom is general
>>>>>> networking and I run the second Gig-E port with Jumbo Frames using a
>>>>>> gigabit
>>>>>> crossover (there is such a thing)
>>>>>> to a Mac Mini with the thunderbolt port running Gig-E and doing iSCSI!
>>>>>> The Mac Mini runs esxi 5.5 and
>>>>>> all the data stores (running various species of Linux) hosted off the
>>>>>> HP-N54L.  It is like a little tiny
>>>>>> SAN, small but perfectly formed....
>>>>>>
>>>>>>
>>>>>> rachel
>>>>>>
>>>>>> --
>>>>>> Rachel Polanskis                 Kingswood, Greater Western Sydney,
>>>>>> Australia
>>>>>> [email protected]             IT consulting, security, programming
>>>>>>           The more an answer costs, the more respect it carries.
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Rachel Polanskis                 Kingswood, Greater Western Sydney,
>>>>>> Australia
>>>>>> [email protected]             IT consulting, security, programming
>>>>>>          The more an answer costs, the more respect it carries.
>>>>>>
>>>>>>
>>>>>>
>>>>> --
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>>>
>>>
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