[Gluster-users] write(filename, ...) implementation

[Soumya Koduri]

On 08/25/2015 12:16 AM, Ivica Siladic wrote:
> Thanks for the answer. I’ve already tried that earlier and I’ve got 2x performance boost as compared to glfs_creat/glfs_write/glfs_close sequence (which gives 4x boost compared to mounted volume).
>
> But, within my loop just glfs_h_open/glfs_h_close calls lasts 2 times longer than glfs_h_anonymous_write alone. So I was guessing that there are some RPC calls behind glfs_h_open/glfs_h_close calls which could be avoided.
>
But you do not need glfs_h_open/glfs_h_close to use anonymous write 
fops. If the file is already present, below APIs are sufficient -
'glfs_h_lookupat' - to get 'glfs_object' given file path.
'glfs_h_anonymous_write' - takes above handle as one of the inputs.

Thanks,
Soumya

> Ivica
>
>> On 24 Aug 2015, at 20:02, Soumya Koduri <skoduri at redhat.com> wrote:
>>
>>
>>
>> On 08/24/2015 11:24 PM, Ivica Siladic wrote:
>>> Hi,
>>>
>>> I'm doing a lot of small writes to distributed/replicated Gluster volume. The performance I'm getting is not acceptable. Interestingly, I'm getting doubled speed boost if I use libgfsapi instead of kernel volume mount.
>>>
>>> My guess is that I could get significant boost if I could reduce RPC roundtrips somehow. So, instead of open->write->close sequence I'd like to use single write(filename, ...) call.
>>>
>>> Can someone point me to the relevant places in Gluster source code and briefly explain how to acomplish that? I really need just some rough ideas.
>>>
>> This can be done using anonymous fd write. There are APIs exported by libgfapi to do anonymous write (glfs_h_anonymous_write). Please refer to 'tests/basic/gfapi/anonymous_fd_read_write.c' regarding its usage.
>>
>> Thanks,
>> Soumya
>>
>>> Ivica
>>> _______________________________________________
>>> Gluster-users mailing list
>>> Gluster-users at gluster.org
>>> http://www.gluster.org/mailman/listinfo/gluster-users
>>>
>