Low performance

[Rainer Pietsch]

Am 04.01.2012 10:46, schrieb Hendrik Visage:
> On Tue, Jan 3, 2012 at 3:42 PM, R. Pietsch <rp.rsync at pcs-at.com> wrote:
>> Hi!
>>
>> I do a rsync between 2 machines. The throughput is only 2 MByte/Sec.
>>
>> Each machine is a Supermicro server with
>>    2 x 8 Core Opteron 6128
>>    64 GByte of ECC RAM
>>    1 LSI MegaRAID SAS 9280-24i4e
>>    24 x 2TByte SATA Disks as a RAID6
>>    2 Intel Corporation 82599EB 10-Gigabit SFI/SFP+ Network-cards
>>
>> Both run Ubuntu 11.04 64Bit.
>> Both use rsync version 3.0.7  protocol version 30
>>
>> There are no errors reported.
>> The local read and write rate to the disks is 1,1 GB/s.
>> A network test shows 800MByte/s over the direct coupled network-cards.
>> The CPU-usage is  5 to 7% of one core.
>> Memory-usage is 1703 out of 64557MB.
>> There are no other jobs running on the two machines.
>> The LSI controllers both say: State: Optimal
>>
>>
>> machine A has a rsync-daemon with the following configuration:
>> ----------
>> read only = false
>> use chroot = false
>> hosts allow = 10.99.11.0/24
>> [Daten1]
>>        path = /var/daten1
>>        use chroot = yes
>>        read only = yes
>>        list = yes
>>        uid = root
>>        gid = root
>>        strict modes = yes
>>        ignore errors = no
>>        ignore nonreadable = yes
>>        transfer logging = no
>>        timeout = 600
>>        refuse options = checksum dry-run
>>        dont compress = *
>> ----------
>>
>> machine B runs:
>>
>> /usr/bin/rsync -ax --numeric-ids --delete --delete-excluded \
>>    --exclude-from=/Backup/RB_None.excl \
>>    --link-dest=/Backup/Base/xxxxx \
>>    rsync://root@10.99.11.11/Daten1/ \
>>    /Backup/Base/yyyyyyy \
>>    --no-c --no-z
>>
>> The files are all about 8 MB in size.
>>
>>    8302592 100%    1.98MB/s    0:00:04 (xfer#861, to-check=51173/94679)
>>
>> The same - slow - transfer happens at 1GB and 5GB files.
>>
>>
>> Any ideas what can cause this slow transmission?
>
> You do have jumbo frames enabled on both servers and the network
> equipment in between?
>
> Do check the TCP/IP stack parameters, as most bandwidth testing is
> done with UDP.
Jumbo frames are NOT enabled - (they cause trouble with samba) and the
test is done with netperf and tcp.
The result is
-----------------------
TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.99.11.11
(10.99.11.11) port 0 AF_INET : demo
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.00    7300.70

----------------------- 
So we get 7.3 GBit with a tcp-stream - rawly 800MByte/sec


-- 
Mit freundlichen Grüßen / best regards

Ing. Rainer Pietsch
----------------------------------------------------------
PCS - Pichler Computer Systeme
Inh. Claudia Pichler-Pietsch
Hauptplatz 10
A-2751 Steinabrückl
Österreich / Austria
----------------------------------------------------------
mail:  r.pietsch at pcs-at.com
web:   http://www.pcs-at.com
tel.:  +43 (2622) 420 19 / 15
mobil: +43 (676) 31 242 69
fax:   +43 (2622) 420 19 / 20
----------------------------------------------------------