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items: *SOLVED* SMP kernel vs PAE
items: Re: SMP kernel vs PAE

*SOLVED* SMP kernel vs PAE
type: item
description: I have a Dell PowerEdge 1900 with 6G of Ram and a quadcore processor. After reviewing the different kernel flavors ( http://wiki.openvz.org/Different_kernel_flavors_%28UP%2C_SMP %2C_ENTERPRISE%2C_ENTNOSPLIT%29) I chose the PAE kernel, which hangs on boot. So I decided to fall back to the SMP kernel. top shows 6G of Ram available. should I bother trying to get the PAE kernel working? -Jon
creator: jpastore
date: 2007-07-19T22:29:35-00:00

Re: SMP kernel vs PAE
type: item
description: 1. what kernel version have you used? the answers/questions depend on this 2. i686 or x86-64? I assume 1st. 3. it is binary kernel from openvz.org or compiled by yourself?
creator: dev
date: 2007-07-20T07:02:13-00:00

Re: SMP kernel vs PAE
type: item
description: uname -a Linux HOSTNAME-OMITTED 2.6.18-ovz028stab035.1-smp #1 SMP Sat Jun 9 12:09:51 MSD 2007 x86_64 x86_64 x86_64 GNU/Linux rpm -qa |grep ovz ovzkernel-2.6.18-8.1.4.el5.028stab035.1 ovzkernel-PAE-2.6.18-8.1.4.el5.028stab035.1 kernel-smp-2.6.18-ovz028stab035.1 I followed the instructions from the wiki and after finishing the instructions I found another set of work around instructions for dealing with x86_64. I did not compile them myself I used yum to fetch them from the openvz repository. Thanks
creator: jpastore
date: 2007-07-20T14:09:08-00:00

Re: SMP kernel vs PAE
type: item
description: PAE kernel is for i686 only. it has even i686 in rpm name For x86-64 there is only one RHEL5 kernel flavour and it's SMP by default. So your currently loaded kernel (2.6.18-ovz028stab035.1-smp as shown by uname output) is the right choice for you.
creator: dev
date: 2007-07-20T14:19:56-00:00

Re: SMP kernel vs PAE
type: item
description: Thank you I didn't realize it was i686 only. I only tried to get it work when I realized I had 6G of ram and the chart stated that over 4G you should PAE. Am I going to fully utilize the 6G of ram with the SMP kernel? I see that it recognizes it, but the wiki states otherwise.
creator: jpastore
date: 2007-07-20T14:27:46-00:00

Re: SMP kernel vs PAE
type: item
description: there is no 4GB limit on x86-64, so the whole RAM will be used. there is a note in wiki Note: When using a 64-bit processor and operating system, you need only select the SMP or non-SMP version. 64-bit linux can access the entire 64Gb of ram in ZONE_NORMAL (low memory). PAE and 4GB/4GB splitting are only needed for 32-bit OS, and so are not necessary and are disabled by default in 64-bit kernels. And I've also added the table in question is i686-specific. Sorry for the confusion :/
creator: dev
date: 2007-07-20T14:31:16-00:00

Re: SMP kernel vs PAE
type: item
description: No problem. Thank you for the clarification!
creator: jpastore
date: 2007-07-20T14:41:22-00:00