Bug 705989 - performance regression on tcp_stream throughput
Summary: performance regression on tcp_stream throughput
Keywords:
Status: CLOSED NOTABUG
Alias: None
Product: Red Hat Enterprise Linux 5
Classification: Red Hat
Component: kernel
Version: 5.7
Hardware: Unspecified
OS: Unspecified
high
high
Target Milestone: rc
: ---
Assignee: Andy Gospodarek
QA Contact: Red Hat Kernel QE team
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2011-05-19 06:00 UTC by Quan Wenli
Modified: 2014-06-29 23:03 UTC (History)
5 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2011-06-09 14:54:16 UTC
Target Upstream Version:


Attachments (Terms of Use)

Description Quan Wenli 2011-05-19 06:00:32 UTC
Description of problem:

performance regression of tcp_stream throughput between kernel-2.6.18-259 and kernel-2.6.18-260.While testing,I disabled tso and enable gso on host and external host.

kernel-version       Throughput 10^6bits/sec (TCP_STREAM)
2.6.18-260.el5       8677.11 
2.6.18-259.el5       2048.93 

Version-Release number of selected component (if applicable):

kernel-2.6.18-260.el5
kernel-2.6.18-259.el5

How reproducible:
100%

Steps to Reproduce:
1.run netserver on rhel 5.7 host with kernel-2.6.18-259.el5.
2.run netperf on ex-host 
./netperf -H 192.168.0.11 -l 60 
TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.0.11 (192.168.0.11) port 0 AF_INET
Recv   Send    Send                          
Socket Socket  Message  Elapsed              
Size   Size    Size     Time     Throughput  
bytes  bytes   bytes    secs.    10^6bits/sec  

 87380  16384  16384    60.00    8677.11
3.switching to kernel-2.6.18-260.el5 on host.  
4.run netperf again on ex-host
./netperf -H 192.168.0.11 -l 60 
TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.0.11 (192.168.0.11) port 0 AF_INET
Recv   Send    Send                          
Socket Socket  Message  Elapsed              
Size   Size    Size     Time     Throughput  
bytes  bytes   bytes    secs.    10^6bits/sec  

 87380  16384  16384    60.01    2048.93
  
Actual results:


Expected results:


Additional info:

ethtool -k eth2
Offload parameters for eth2:
Cannot get device udp large send offload settings: Operation not supported
rx-checksumming: on
tx-checksumming: on
scatter-gather: on
tcp segmentation offload: off
udp fragmentation offload: off
generic segmentation offload: on
generic-receive-offload: on


ethtool eth2
Settings for eth2:
	Supported ports: [ FIBRE ]
	Supported link modes:   1000baseT/Full 
                               10000baseT/Full 
	Supports auto-negotiation: Yes
	Advertised link modes:  1000baseT/Full 
	                        10000baseT/Full 
	Advertised auto-negotiation: Yes
	Speed: 10000Mb/s
	Duplex: Full
	Port: FIBRE
	PHYAD: 0
	Transceiver: external
	Auto-negotiation: on
	Supports Wake-on: d
	Wake-on: d
	Current message level: 0x00000007 (7)
	Link detected: yes

ethtool -i eth2
driver: ixgbe
version: 3.2.9-k2
firmware-version: 0.9-3
bus-info: 0000:0f:00.0

Comment 4 Andy Gospodarek 2011-06-08 20:07:01 UTC
There are no ixgbe changes between -259 and -260, so I do not suspect this is specifically a problem on ixgbe.  What other 10GbE interfaces were tested and did not show the issue?

Comment 6 Andy Gospodarek 2011-06-08 20:23:12 UTC
BTW, we are also tracking what may or may not be an ixgbe issue in bug 706757.

Comment 7 Quan Wenli 2011-06-09 07:39:12 UTC
(In reply to comment #4)
> There are no ixgbe changes between -259 and -260, so I do not suspect this is
> specifically a problem on ixgbe.  What other 10GbE interfaces were tested and
> did not show the issue?

As -260 was removed from brew,I do the comparison again between -259 and -266. Keep the netperf server with -259 kernel ,switching netperf sender with kernel from -259 to -266.The results show there is no regression now.
netperf ci : ./netperf -H 192.168.0.11 -l 60 (with default message size :16384 bytes)


Sender             Receiver      |  -259   |    -266   |
----------------+----------------+---------+-----------+  
tso on gso off    rsc on gro on    8700.17    8716.22
----------------+----------------+---------+-----------+
tso on gso off    rsc on gro off   8804.30    8767.13
----------------+----------------+---------+-----------+
tso off gso on    rsc on gro on    7494.25    7582.54
----------------+----------------+---------+-----------+
tso on gso off    rsc off gro on   6657.81    6627.00
----------------+----------------+---------+-----------+
tso on gso off    rsc off gro off  6258.57    6591.09
----------------+----------------+---------+-----------+
tso off gso on    rsc off gro on   6218.01    6568.12
----------------+----------------+---------+-----------+

Comment 9 Andy Gospodarek 2011-06-09 14:54:16 UTC
Closing as NOTABUG based on results in comment #7.


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