bcache not works?

bcache not works?

[Vasiliy Tolstov]

I have this setup:
/dev/md127 - raid1 with one sata 3Tb drive
/dev/sdb SSD disk with 240 Gb

I'm succeseful create bcache0 device and format it to ext4.

/dev/bcache0 /var/lib/libvirt/images ext4
rw,relatime,journal_checksum,journal_async_commit,errors=remount-ro,min_batch_time=15000,max_batch_time=60000,data=ordered
0 0

After that i'm install kvm virtual machine and tries to create some
activity via iozone fio and other. But stats says nothing.

What i miss?

root@node03:~# cat
/sys/fs/bcache/76907875-ef3b-48b1-8531-f880e64487a8/stats_day/*
0
0
0
0
0
0
0
0



-- 
Vasiliy Tolstov,
e-mail: v.tolstov-+9FY0jupvH6HXe+LvDLADg@public.gmane.org
jabber: vase-+9FY0jupvH6HXe+LvDLADg@public.gmane.org

Re: bcache not works?

[Vasiliy Tolstov]

2013/10/16 Vasiliy Tolstov <v.tolstov-+9FY0jupvH6HXe+LvDLADg@public.gmane.org>:
> I have this setup:
> /dev/md127 - raid1 with one sata 3Tb drive
> /dev/sdb SSD disk with 240 Gb
>
> I'm succeseful create bcache0 device and format it to ext4.
>
> /dev/bcache0 /var/lib/libvirt/images ext4
> rw,relatime,journal_checksum,journal_async_commit,errors=remount-ro,min_batch_time=15000,max_batch_time=60000,data=ordered
> 0 0
>
> After that i'm install kvm virtual machine and tries to create some
> activity via iozone fio and other. But stats says nothing.
>
> What i miss?


Anybody knowns?
P.S. I'm using kernel 3.11.4. How can i enable bcache?

-- 
Vasiliy Tolstov,
e-mail: v.tolstov-+9FY0jupvH6HXe+LvDLADg@public.gmane.org
jabber: vase-+9FY0jupvH6HXe+LvDLADg@public.gmane.org

Re: bcache not works?

[Gabriel de Perthuis]

Le 16/10/2013 06:22, Vasiliy Tolstov a écrit :
> I have this setup:
> /dev/md127 - raid1 with one sata 3Tb drive
> /dev/sdb SSD disk with 240 Gb
> 
> I'm succeseful create bcache0 device and format it to ext4.
> 
> /dev/bcache0 /var/lib/libvirt/images ext4
> rw,relatime,journal_checksum,journal_async_commit,errors=remount-ro,min_batch_time=15000,max_batch_time=60000,data=ordered
> 0 0
> 
> After that i'm install kvm virtual machine and tries to create some
> activity via iozone fio and other. But stats says nothing.
> 
> What i miss?

Maybe the cache isn't attached to the backing device?

If you initialise both with the same make-bcache call they are
immediately attached, otherwise you need to connect them:

http://evilpiepirate.org/git/linux-bcache.git/tree/Documentation/bcache.txt?h=bcache-dev#n80

Re: bcache not works?

[Vasiliy Tolstov]

2013/10/17 Gabriel de Perthuis <g2p.code-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>:
> Maybe the cache isn't attached to the backing device?
>
> If you initialise both with the same make-bcache call they are
> immediately attached, otherwise you need to connect them:
>
> http://evilpiepirate.org/git/linux-bcache.git/tree/Documentation/bcache.txt?h=bcache-dev#n80

As i see its all attached.
[  180.459041] bcache: register_bcache() error opening /dev/md127:
device already registered
[  180.459060] bcache: register_bcache() error opening /dev/sdb:
device already registered


-- 
Vasiliy Tolstov,
e-mail: v.tolstov-+9FY0jupvH6HXe+LvDLADg@public.gmane.org
jabber: vase-+9FY0jupvH6HXe+LvDLADg@public.gmane.org

Re: bcache not works?

[Vasiliy Tolstov]

2013/10/17 Vasiliy Tolstov <v.tolstov-+9FY0jupvH6HXe+LvDLADg@public.gmane.org>:
>> Maybe the cache isn't attached to the backing device?
>>
>> If you initialise both with the same make-bcache call they are
>> immediately attached, otherwise you need to connect them:
>>
>> http://evilpiepirate.org/git/linux-bcache.git/tree/Documentation/bcache.txt?h=bcache-dev#n80
>
> As i see its all attached.
> [  180.459041] bcache: register_bcache() error opening /dev/md127:
> device already registered
> [  180.459060] bcache: register_bcache() error opening /dev/sdb:
> device already registered


Ohh. Sorry. I'm create already created bcache device and its not
attached. After i'm attach  i see that stats changed..
Thanks!

-- 
Vasiliy Tolstov,
e-mail: v.tolstov-+9FY0jupvH6HXe+LvDLADg@public.gmane.org
jabber: vase-+9FY0jupvH6HXe+LvDLADg@public.gmane.org