P. Remek <p.remek1@xxxxxxxxxxxxxx> schrieb:
> Not sure if it helps, but here is it:
>
> root@lab1:/mnt/vol1# btrfs filesystem df /mnt/vol1/
> Data, RAID10: total=116.00GiB, used=110.03GiB
> Data, single: total=8.00MiB, used=0.00
> System, RAID1: total=8.00MiB, used=16.00KiB
> System, single: total=4.00MiB, used=0.00
> Metadata, RAID1: total=2.00GiB, used=563.72MiB
> Metadata, single: total=8.00MiB, used=0.00
> unknown, single: total=192.00MiB, used=0.00
This looks completely different to my output. Do you use the latest btrfs-
progs?
$ btrfs --version
Btrfs v3.18.2
$ btrfs fi us /
Overall:
Device size: 2.71TiB
Device allocated: 1.50TiB
Device unallocated: 1.21TiB
Used: 1.37TiB
Free (estimated): 1.33TiB (min: 745.87GiB)
Data ratio: 1.00
Metadata ratio: 2.00
Global reserve: 512.00MiB (used: 0.00B)
Data,RAID0: Size:1.49TiB, Used:1.36TiB
/dev/bcache0 507.00GiB
/dev/bcache1 507.00GiB
/dev/bcache2 507.00GiB
Metadata,RAID1: Size:6.00GiB, Used:3.99GiB
/dev/bcache0 4.00GiB
/dev/bcache1 4.00GiB
/dev/bcache2 4.00GiB
System,RAID1: Size:32.00MiB, Used:100.00KiB
/dev/bcache1 32.00MiB
/dev/bcache2 32.00MiB
Unallocated:
/dev/bcache0 414.51GiB
/dev/bcache1 414.48GiB
/dev/bcache2 414.48GiB
> On Mon, Feb 9, 2015 at 8:56 PM, Kai Krakow <hurikhan77@xxxxxxxxx> wrote:
>> P. Remek <p.remek1@xxxxxxxxxxxxxx> schrieb:
>>
>>> Hello,
>>>
>>> I am benchmarking Btrfs and when benchmarking random writes with fio
>>> utility, I noticed following two things:
>>>
>>> 1) On first run when target file doesn't exist yet, perfromance is
>>> about 8000 IOPs. On second, and every other run, performance goes up
>>> to 70000 IOPs. Its massive difference. The target file is the one
>>> created during the first run.
>>>
>>> 2) There are windows during the test where IOPs drop to 0 and stay 0
>>> about 10 seconds and then it goes back again, and after couple of
>>> seconds again to 0. This is reproducible 100% times.
>>>
>>> Can somobody shred some light on what's happening?
>>
>> I'm not an expert or dev but it's probably due to btrfs doing some
>> housekeeping under the hood. Could you check the output of "btrfs
>> filesystem usage /mountpoint" while running the test? I'd guess there's
>> some pressure on the global reserve during those times.
>>
>>> Command: fio --randrepeat=1 --ioengine=libaio --direct=1
>>> --gtod_reduce=1 --name=test9 --filename=test9 --bs=4k --iodepth=256
>>> --size=10G --numjobs=1 --readwrite=randwrite
>>>
>>> Environment:
>>> CPU: dual socket: E5-2630 v2
>>> RAM: 32 GB ram
>>> OS: Ubuntu server 14.10
>>> Kernel: 3.19.0-031900rc2-generic
>>> btrfs tools: Btrfs v3.14.1
>>> 2x LSI 9300 HBAs - SAS3 12/Gbs
>>> 8x SSD Ultrastar SSD1600MM 400GB SAS3 12/Gbs
>>>
>>> Regards,
>>> Premek
>>
>> --
>> Replies to list only preferred.
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
>> the body of a message to majordomo@xxxxxxxxxxxxxxx
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Replies to list only preferred.
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
