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From: shally verma <shallyvermacavium@gmail.com>
To: Timofey Titovets <nefelim4ag@gmail.com>
Cc: linux-btrfs <linux-btrfs@vger.kernel.org>,
	"Verma, Shally" <shally.verma@cavium.com>
Subject: Re: using fio to test btrfs compression
Date: Wed, 20 Sep 2017 14:29:08 +0530	[thread overview]
Message-ID: <CAP9W88ip0ef7yFc3-o8LNO=WsBjhpADbSuzQoppz6yC5KpRTQg@mail.gmail.com> (raw)
In-Reply-To: <CAGqmi75DoErKwwHu7+abu62sUbbEgjMZ1ExzpCpQ68JKmTF==g@mail.gmail.com>

On Wed, Sep 20, 2017 at 2:25 PM, Timofey Titovets <nefelim4ag@gmail.com> wrote:
> 2017-09-20 11:44 GMT+03:00 shally verma <shallyvermacavium@gmail.com>:
>> One more catch... I am initiating fio from non-btrfs filesystem i.e.
>> pwd is ext4 based fs where as mount point is btrfs.
>> Could that make difference?
>>
>>> Thanks
>>> Shally
>
> Only matter are where you store test file =)
> If you store test file on btrfs, pwd does nothing.
>

Then steps listed in previous mail should work right?  Am listing them
again here:

" ----
>
> 1. mount -t btrfs -o compress-force=zlib /dev/sdb1 mnt
>
> 2. fio --directory=mnt/ --numjobs=1 --direct=0 --buffered=1 --bs=64k
> --rw=write --iodepth=128 --name=test --size=1G
> --buffer_compress_percentage=100 --buffer_pattern=0xFF --refill_buffer
> --ioengine=libaio
>
> 1GN file written uncompressed. Here no compression invoked (though
> compress-force=zlib)
>
> 3. cp mnt/test ./ --> copy back fio generated test file from btrfs
> mount point to local drive
>
> 4. hex dump test file (all FFs) -- confirmed that data is compressible
> no random data.
>
> 5. cp test mnt/  --> now, copy same test again back to mount point
> (reverse of step 3) . Now, here I see during copying compression is
> invoked.
>
> I am using kernel 4.9 and compress-foce is said to be working for
> kernel > 2.13 from wiki ... so I wonder what's so special with cp
> command which is not happening during fio writes???

"-----

Thanks
Shally


> --
> Have a nice day,
> Timofey.

  reply	other threads:[~2017-09-20  8:59 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-09-18  7:36 using fio to test btrfs compression shally verma
2017-09-18  8:26 ` Timofey Titovets
2017-09-18 13:28   ` shally verma
2017-09-18 13:41     ` Timofey Titovets
2017-09-20  8:36       ` shally verma
2017-09-20  8:44         ` shally verma
2017-09-20  8:55           ` Timofey Titovets
2017-09-20  8:59             ` shally verma [this message]
2017-09-20  9:36               ` Timofey Titovets
2017-09-20 10:13                 ` shally verma
2017-09-20 10:30                   ` Timofey Titovets
2017-09-20 11:10                     ` shally verma
2017-09-21 11:42                       ` Duncan
     [not found]                       ` <CAGqmi74eviuSf=LL7sGEJnH1YYqu_pHdaGDvq4Qdr4aSpvqxkQ@mail.gmail.com>
2017-09-22  5:33                         ` shally verma
2017-09-22 17:05                           ` Timofey Titovets
2017-09-21 15:26 ` Liu Bo

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