[Ocfs2-users] Ofcs2 Questions!

[Henrique Fernandes]

Thanks for the tips.

So you are saying that if both nodes have same load, inscrease comit time
will not make any diferences ?



[]'sf.rique


On Wed, Feb 2, 2011 at 11:54 PM, Sunil Mushran <sunil.mushran at oracle.com>wrote:

>  # grep "Resources" /sys/kernel/debug/o2dlm/UUID/dlm_state
> Lock Resources: 20713 (1139459)
>
> The first number is number of live resources. Second the number
> of resources created for the life of the domain.
>
> If you see the the number of resources levelling off but the second
> number incrementing, that _could_ mean that you could benefit with
> a larger cache. But you have to supplement that number with the
> workload. Say you are deleting and creating files. In that case, you
> will see the same number movement but not because of the cache limit.
>
> We are in the process of adding more counters to provide more visibility
> to the users.
>
> Well, using any software without support has its risks.
>
> Using noatime will help. Increasing commit will help if workload if largely
> from one node only.
>
>
> On 02/02/2011 05:10 PM, Henrique Fernandes wrote:
>
> centos 5.5
> ocfs2 1.4
> The mail solution, dovecot+postifx+mailscaner  uses about 1 gb the machine
> has 1.5 in my tests i am rising it to 3gb so it have 2gb of cached
>
> How many memory do you thing i should separeted for cache ?
>
> When we made some tests  ocfs2 1.4 had better performance than 1.6 but or
> tests were very simple, an script that writes lots of files and anothe rone
> that reads it.
>
> And it is a problem to have ocfs2 1.6 in ths centos!!
>
> Should i use ocfs2 in production ?
>
> how about the commit and noatime configs ??
>
>
> thanks!!
>
> []'sf.rique
>
>
> On Wed, Feb 2, 2011 at 9:27 PM, Sunil Mushran <sunil.mushran at oracle.com>wrote:
>
>>  version? distro?
>>
>> This workload will benefit a lot with the indexed directories available in
>> ocfs2 1.6 (and mainline and sles11).
>>
>> The other thing to check is the amount memory in the virtual machines.
>> File systems need memory to cache the inodes. If memory is lacking,
>> the inodes are freed and have to be re-read from disk time and again.
>> While this is a problem even in a local fs, it is a bigger problem in a
>> cfs
>> as a cfs needs to do lock mastery for the same inode time and again.
>>
>>
>> On 02/02/2011 01:09 PM, Henrique Fernandes wrote:
>>
>>  Hello,
>>
>> First of all, i am new at the list and i have several questions about
>> ocfs2 performance.
>>
>> Where i am working i am having huge performance problens with ocfs2.
>>
>> Let me tell my envoriment.
>>
>> 3 Xen VirtualMachines withs ocfs2 mounting an LUN exported over iSCSI. (
>> acctualy 3 LUNS, 3 ocfs2 clusters )
>>
>> I am not the one who configured the envoriment, but it is making the
>> performance of my MAIL system to bad.
>>
>> Have about 9k accounts but only 4k are active. It is a maildir system. (
>> postfix + dovecot )
>>
>> Now that this performance problens are afecting my system i am gonna try
>> help to tunning the ocfs2.
>>
>> Pretty much all default settings.
>>
>> OCFS2 is configured to write with ordered mode. We know that changing to
>> writeback will make performance much better, but we are not considering lose
>> anydata, so it i snot an option.
>>
>> Now we are going to implemente noatime options in mount. This make better
>> performace ?
>>
>> Other one, how about the commit mount options ? The default is set to 5s
>> if i increse it how is the potential data loss in case we lost lose power?
>>
>> Does anyone have any other paramenter that should help us ?
>>
>> Another info, the inscremental backup is taking 10 to 12 hours.
>>
>> All nodes have VERY high I/O wait.
>>
>> Thanks to all!!
>>
>> If you could tell me any doc that i sould read would be nice to!
>>
>>
>>
>>
>>
>>
>> []'sf.rique
>>
>>
>> _______________________________________________
>> Ocfs2-users mailing listOcfs2-users at oss.oracle.comhttp://oss.oracle.com/mailman/listinfo/ocfs2-users
>>
>>
>>
>
>
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