1.
Performance comparisson of
Distributed File Systems
GlusterFS
XfreemFS
FhgFS
Marian Marinov
CEO of 1H Ltd.

2.
What have I tested?
➢ GlusterFS
http://glusterfs.org
➢ XtremeFS
http://www.xtreemfs.org/
➢ FhgFS
http://www.fhgfs.com/cms/ Fraunhofer
➢ Tahoe-LAFS http://tahoe-lafs.org/
➢ PlasmaFS
http://blog.camlcity.org/blog/plasma4.html

3.
What will be compared?
➢ Ease of install and configuration
➢ Sequential write and read (large file)
➢ Sequential write and read (many same size, small files)
➢ Copy from local to distributed
➢ Copy from distributed to local
➢ Copy from distributed to distributed
➢ Creating many random file sizes (real cases)
➢ Creating many links (cp -al)

4.
Why only on 1Gbit/s ?
➢ It is considered commodity
➢ 6-7 years ago it was considered high performance
➢ Some projects have started around that time
➢ And last, I only had 1Gbit/s switches available for the
tests

5.
Lets get the theory first
1Gbit/s has ~950Mbit/s usable Bandwidth
Wikipedia - Ethernet frame
Which is 118.75 MBytes/s usable speed
iperf tests - 512Mbit/s -> 65MByte/s
There are many 1Gbit/s adapters
that can not go beyond 70k pps
iperf tests - 938Mbit/s -> 117MByte/s
hping3 tcp pps tests
- 50096 PPS (75MBytes/s)
- 62964 PPS (94MBytes/s)

6.
Verify what the hardware can deliver locally
# echo 3 > /proc/sys/vm/drop_caches
# time dd if=/dev/zero of=test1 bs=XX count=1000
# time dd if=test1 of=/dev/null bs=XX
bs=1M
Local write 141MB/s
bs=1M
Local read 228MB/s real 0m4.605s
bs=100K Local write 141MB/s
real 0m7.493s
real 0m7.639s
bs=100K Local read 226MB/s real 0m4.596s
bs=1K
Local write 126MB/s
real 0m8.354s
bs=1K
Local read 220MB/s real 0m4.770s
* most distributed filesystems write with the speed of the slowest member node

7.
Linux Kernel Tuning
sysctl
net.core.netdev_max_backlog=2000
Default 1000
Congestion control
selective acknowledgments
net.ipv4.tcp_sack=0
net.ipv4.tcp_dsack=0
Default enabled

8.
Linux Kernel Tuning
TCP memory optimizations
min pressure max
net.ipv4.tcp_mem=41460 42484 82920
min default max
net.ipv4.tcp_rmem=8192 87380 6291456
net.ipv4.tcp_wmem=8192 87380 6291456
Double the tcp memory

9.
Linux Kernel Tunning
➢ net.ipv4.tcp_syncookies=0
default 1
➢ net.ipv4.tcp_timestamps=0
default 1
➢ net.ipv4.tcp_app_win=40
default 31
➢ net.ipv4.tcp_early_retrans=1 default 2
* For more information - Documentation/networking/ip-sysctl.txt

10.
More tuning :)

11.
Ethernet Tuning
➢ TSO (TCP segmentation offload)
➢ GSO (generic segmentation offload)
➢ GRO/LRO (Generic/Large receive offload)
➢ TX/RX checksumming
➢ ethtool -K ethX tx on rx on tso on gro on lro on

12.
GlusterFS setup
1. gluster peer probe nodeX
2. gluster volume create NAME replica/stripe 2
node1:/path/to/storage node2:/path/to/storage
3. gluster volume start NAME
4. mount -t glusterfs nodeX:/NAME /mnt

13.
XtreemeFS setup
1. Configure and start the directory server(s)
2. Configure and start the metadata server(s)
3. Configure and start the storage server(s)
4. mkfs.xtreemfs localhost/myVolume
5. mount.xtreemfs localhost/myVolume /some/local/path

14.
FhgFS setup
1. Configure /etc/fhgfs/fhgfs-*
2. /etc/init.d/fhgfs-client rebuild
3. Start daemons fhgfs-mgmtd fhgfs-meta fhgfs-storage
fhgfs-admon fhgfs-helperd
4. Configure the local client on all machines
5. Start the local client fhgfs-client

15.
Tahoe-LAFS setup
➢ Download
➢ python setup.py build
➢ export PATH=”$PATH:$(pwd)/bin”
➢ Install sshfs
➢ Setup ssh rsa key

16.
Tahoe-LAFS setup
➢ mkdir /storage/tahoe
➢ cd /storage/tahoe && tahoe create-introducer .
➢ tahoe start .
➢ cat /storage/tahoe/private/introducer.furl
➢ mkdir /storage/tahoe-storage
➢ cd /storage/tahoe-storage && tahoe create-node .
➢ Add the introducer.furl to tahoe.cfg
➢ Add [sftpd] section to tahoe.cfg

17.
Tahoe-LAFS setup
➢ Configure the shares
➢ shares.needed = 2
➢ shares.happy = 2
➢ shares.total = 2
➢ Add accounts to the accounts file
# This is a password line, (username, password, cap)
alice password
URI:DIR2:ioej8xmzrwilg772gzj4fhdg7a:wtiizszzz2rgmczv4wl6bqvbv33ag4kvbr6prz3u6w3geixa6m6a

18.
Statistics

19.
Sequential write
GlusterFS
dd if=/dev/zero of=test1 bs=1M count=1000
dd if=/dev/zero of=test1 bs=100K count=10000
dd if=/dev/zero of=test1 bs=1K count=1000000
500
XtreemeFS
FhgFS
467
450
400
MBytes/s
358
342
350
300
250
200
150
112.6
106.3
100
50
0
43.53
13.7
59.83
1.7
1K
* higher is better
100K
1M

20.
Sequential read
GlusterFS
XtreemeFS
FhgFS
dd if=/mnt/test1 of=/dev/zero bs=XX
250
225
214.6
MBytes/s
200
185.3
209
181.3
179.6
150
105
105.6
100K
1M
100
74.6
50
0
1K
* higher is better

21.
Sequential write (local to cluster)
GlusterFS
XtreemeFS
FhgFS
Tahoe-LAFS
dd if=/tmp/test1 of=/mnt/test1 bs=XX
120
96.33
100
93.7
87.26
76.7
MBytes/s
80
70.3
57.96
60
43.7
40
20
11.36
5.41
0
1K
* higher is better
100K
1M

22.
Sequential read (cluster to local)
GlusterFS
XtreemeFS
FhgFS
dd if=/mnt/test1 of=/tmp/test1 bs=XX
90
80
83.76
85.4
82.56
77.5
74.83
72.56
66.1
70
67.13
100K
1M
MBytes/s
60
50
40
30
20
10
0
1K
* higher is better

23.
Sequential read/write (cluster to cluster)
GlusterFS
XtreemeFS
FhgFS
dd if=/mnt/test1 of=/mnt/test2 bs=XX
120
103.96
100
94.4
93.73
MBytes/s
80
62.7
59.6
60
40
20
36
40.7
11.8
0
1K
* higher is better
100K
1M

24.
Joomla tests (local to cluster)
# for i in {1..100}; do time cp -a /tmp/joomla /mnt/joomla$i; done
70
62.83
60
seconds
50
40
31.42
30
19.26
20
10
0
copy
* lower is better
28MB
6384 inodes
GlusterFS
XtreemeFS
FhgFS

25.
Joomla tests (cluster to local)
# for i in {1..100}; do time cp -a /mnt/joomla /tmp/joomla$i; done
250
200.73
seconds
200
150
100
50
39.7
19.26
0
copy
* lower is better
28MB
6384 inodes
GlusterFS
XtreemeFS
FhgFS

26.
Joomla tests (cluster to cluster)
# for i in {1..100}; do time cp -a joomla joomla$i; done
# for i in {1..100}; do time cp -al joomla joomla$i; done
28MB
6384 inodes
GlusterFS
XtreemeFS
FhgFS
300
265.02
250
seconds
200
150
113.46
100
50
89.52
76.44
51.31
22.53
0
copy
* lower is better
link

27.
Conclusion
➢Distributed FS for large file storage – FhgFS
➢ General purpose distributed FS - GlusterFS
* lower is better

28.
QUESTIONS?
Marian Marinov
<mm@1h.com>
http://www.1h.com
http://hydra.azilian.net
irc.freenode.net hackman
ICQ: 7556201
Jabber: hackman@jabber.org