[Gluster-devel] accessing glusterfs mounted share - really slow

[Matthias Albert]

Hi all,

first of all, I've to say that gluterfs is really cool and absolutly
great. I'm not a cluster filesystem specialist but I tested/configured
openafs and lustre and both of them are so huge and complicated.
As I saw glusterfs and played a little bit with it, I was really
surprised how easy it is to setup a cluster filesystem without extra
acl's, without formatting the new filesystem without a
metadata/objectserver :-). Thanks a lot for this.

Of course I've some questions :-).

I've setup 4 glusterfsd server, each of them with a storage of about
400-500 Gig pre-tax.
On client side  I made different afr's over my remote volumes and
finally a unify over the afr's. Readahead and writebehind is also enabled.

Everything is working fine. I can copy "tons" of Gigabytes in my
glusterfs without any problms and also my performance is absolutly great.

But every time I start a "cp" or do a "dd test (to write some testfiles
in the gluster storage) on some of my clients (I've 3 glusterfs clients
one of them is a bacula server which uses the glusterfs as storage)
all access from my glusterfs clients to the mounted share is really
slow. It takes sometimes about 3-4 seconds till my ls is printing the
output of the directory.

e.g.
---snip---
bash# df -h
glusterfs             892G   84G  809G  10% /backup

gsx:/backup/vmware-images # time ll
...
...
real    0m2.863s
user    0m0.004s
sys     0m0.005s
gsx:/backup/vmware-images #
---snap---

Also the "tab completion" in the mounted glusterfs share is really slow.
Access of not mounted glusterfs share is just normal (accessing /etc
/usr/ /root etc. )

Does anyone know these "phenomenon"?

I'm using Debian as distro for all of my servers and Debian and SuSE on
Client side.

glusterfs version: glusterfs--mainline--2.5 patch-459
fuse: fuse-2.7.0-glfs3

If needed I can post my configs, strace outputs of ls -la and so on.

Regards,

  Matthias