Comparison of PAE and Non-PAE 2..4.14 (p8) in high load

["Willi Nüßer" <wilhelm.nuesser@sap.com>]

Hi,

after my first posting to lkml where we compared distributor
provided kernels vs. a plain 2.4.14-pre8 it was pointed
out that between PAE and non-PAE kernels some performance
differences might exist.


We checked this last night and here are the first results.
Again,
a) the relevant quantity dialog steps per second is a
measure for the throughput our application servers runs.
b) our application server and the corresponding database
(SAP DB) run on 4 way Dell, 1 GB at boot time enabled.

Results:
---------

2.4.7 
	2.4.14p8 PAE		2.4.14p4 non- PAE
-------------------------------------------------------------
   1.80		13.42            	15.47
   1.10		13.28            	14.76
   1.20 		14.08            	14.63
   1.26     	13.17            	15.30
   1.35		13.41            	14.51


This means that we did see a performance decrease of about
6 % compared to 2.4.14p8 nonPAE but still 2.4.14p8 is an order
of magnitude faster than 2.4.7

-- 
Best regards
	Willi

-----------------------------------
Willi Nuesser
SAP Linuxlab