On Fri, May 22, 2015 at 06:50:40PM +0800, Paul Guo wrote:
> Hello,
>
> I wrote two simple single-process seq read test case to compare libgfapi and
> fuse. The logic looks like this.
>
> char buf[32768];
> while (1) {
> cnt = read(fd, buf, sizeof(buf));
> if (cnt == 0)
> break;
> else if (cnt > 0)
> total += cnt;
> // No "cnt < 0" was found during testing.
> }
>
> Following is the time which is needed to finish reading a large file.
>
> fuse libgfapi
> direct io: 40s 51s
> non direct io: 40s 47s
>
> The version is 3.6.3 on centos6.5. The result shows that libgfapi is
> obviously slower than the fuse interface although the cpu cycles were saved
> a lot during libgfapi testing. Each test was run before cleaning up all
> kernel pageche&inode&dentry caches and stopping and then starting
> glusterd&gluster (to clean up gluster cache).
>
> I tested direct io because I suspected that fuse kernel readahead
> helped more than the read optimization solutions in gluster. I searched
> a lot but I did not find much about the comparison between fuse and
> libgfapi. Anyone has known about this and known why?
Does your testing include the mount/unmount and/or libgfapi:glfs_init()
parts? Maybe you can share your test programs so that others can try and
check it too?
https://github.com/axboe/fio supports Gluster natively too. That tool
has been developed to test and compare I/O performance results. Does it
give you similar differences?
Niels
_______________________________________________
Gluster-users mailing list
Gluster-users@xxxxxxxxxxx
http://www.gluster.org/mailman/listinfo/gluster-users
