Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 25 Jan 2010 02:29:49 +0200
From:      Dan Naumov <dan.naumov@gmail.com>
To:        Alexander Motin <mav@freebsd.org>
Cc:        freebsd-fs@freebsd.org, Jason Edwards <sub.mesa@gmail.com>, FreeBSD-STABLE Mailing List <freebsd-stable@freebsd.org>, freebsd-questions@freebsd.org
Subject:   Re: 8.0-RELEASE/amd64 - full ZFS install - low read and write disk  performance
Message-ID:  <cf9b1ee01001241629v1f3e1458hc8a5c615308ac2ef@mail.gmail.com>
In-Reply-To: <cf9b1ee01001241614x2ccb818at7631a58cfb143153@mail.gmail.com>
References:  <883b2dc51001240905r4cfbf830i3b9b400969ac261b@mail.gmail.com> <1264368182.00211075.1264355402@10.7.7.3> <4B5CC167.5010604@FreeBSD.org> <cf9b1ee01001241614x2ccb818at7631a58cfb143153@mail.gmail.com>

next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, Jan 25, 2010 at 2:14 AM, Dan Naumov <dan.naumov@gmail.com> wrote:
> On Sun, Jan 24, 2010 at 11:53 PM, Alexander Motin <mav@freebsd.org> wrote=
:
>> Dan Naumov wrote:
>>> This works out to 1GB in 36,2 seconds / 28,2mb/s in the first test and
>>> 4GB in 143.8 seconds / 28,4mb/s and somewhat consistent with the
>>> bonnie results. It also sadly seems to confirm the very slow speed :(
>>> The disks are attached to a 4-port Sil3124 controller and again, my
>>> Windows benchmarks showing 65mb/s+ were done on exact same machine,
>>> with same disks attached to the same controller. Only difference was
>>> that in Windows the disks weren't in a mirror configuration but were
>>> tested individually. I do understand that a mirror setup offers
>>> roughly the same write speed as individual disk, while the read speed
>>> usually varies from "equal to individual disk speed" to "nearly the
>>> throughput of both disks combined" depending on the implementation,
>>> but there is no obvious reason I am seeing why my setup offers both
>>> read and write speeds roughly 1/3 to 1/2 of what the individual disks
>>> are capable of. Dmesg shows:
>>>
>>> atapci0: <SiI 3124 SATA300 controller> port 0x1000-0x100f mem
>>> 0x90108000-0x9010807f,0x90100000-0x90107fff irq 21 at device 0.0 on
>>> pci4
>>> ad8: 1907729MB <WDC WD20EADS-32R6B0 01.00A01> at ata4-master SATA300
>>> ad10: 1907729MB <WDC WD20EADS-00R6B0 01.00A01> at ata5-master SATA300
>>
>> 8.0-RELEASE, and especially 8-STABLE provide alternative, much more
>> functional driver for this controller, named siis(4). If your SiI3124
>> card installed into proper bus (PCI-X or PCIe x4/x8), it can be really
>> fast (up to 1GB/s was measured).
>>
>> --
>> Alexander Motin
>
> Sadly, it seems that utilizing the new siis driver doesn't do much good:
>
> Before utilizing siis:
>
> iozone -s 4096M -r 512 -i0 -i1
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0random
> random =A0 =A0bkwd =A0 record =A0 stride
> =A0 =A0 =A0 =A0 =A0 =A0 =A0KB =A0reclen =A0 write rewrite =A0 =A0read =A0=
 =A0reread =A0 =A0read
> write =A0 =A0read =A0rewrite =A0 =A0 read =A0 fwrite frewrite =A0 fread =
=A0freread
> =A0 =A0 =A0 =A0 4194304 =A0 =A0 512 =A0 28796 =A0 28766 =A0 =A051610 =A0 =
=A050695
>
> After enabling siis in loader.conf (and ensuring the disks show up as ada=
):
>
> iozone -s 4096M -r 512 -i0 -i1
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0random
> random =A0 =A0bkwd =A0 record =A0 stride
> =A0 =A0 =A0 =A0 =A0 =A0 =A0KB =A0reclen =A0 write rewrite =A0 =A0read =A0=
 =A0reread =A0 =A0read
> write =A0 =A0read =A0rewrite =A0 =A0 read =A0 fwrite frewrite =A0 fread =
=A0freread
> =A0 =A0 =A0 =A0 4194304 =A0 =A0 512 =A0 28781 =A0 28897 =A0 =A047214 =A0 =
=A050540

Just to add to the numbers above, exact same benchmark, on 1 disk
(detached 2nd disk from the mirror) while using the siis driver:

                                                            random
random    bkwd   record   stride
              KB  reclen   write rewrite    read    reread    read
write    read  rewrite     read   fwrite frewrite   fread  freread
         4194304     512   57760   56371    68867    74047


- Dan



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?cf9b1ee01001241629v1f3e1458hc8a5c615308ac2ef>