Cpanel 64bit or 32bit PAE Kernal and 12GB RAM?? (CentOs/RedHat)

vissa

Well-Known Member
May 12, 2003
46
0
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I'm getting a new server with 12GB ram. It will run several large vbulletin forums (one at 2.5Mil posts) w/vbseo, a classifieds script, and some static websites. We use XCACHE php accelerator (which I understand does work in 64 bit). The server does a bit of everything (email, web, mysql, php, etc), but all sites are controlled by me and we don't allow access to cpanel/whm to anyone but me.

Question: Is Cpanel finally ready for a 64bit OS? I will likely have CentOs 5 installed. I have been told by more than one datacenter that they recommend 32bit with PAE kernel for Cpanel w/12GB support. They claim that is more stable. I know there have been 64bit problems with Cpanel and/or updates in the past, but I *thought* those had been worked out. Can I get an official response here or one from people with actual experience?

From what I understand, the limits of PAE kernel are some performance penalties for memory mapping (in addition to the 32bit vs 64 bit one), and programs can only each access 4GB at a time.. That's not a huge deal for most things, but it might be nice to have the option of allocating more than 4GB to mysql.

Thank you!
 
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cPanelNick

Administrator
Staff member
Mar 9, 2015
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cPanel Access Level
DataCenter Provider
I'm getting a new server with 12GB ram. It will run several large vbulletin forums (one at 2.5Mil posts) w/vbseo, a classifieds script, and some static websites. We use XCACHE php accelerator (which I understand does work in 64 bit). The server does a bit of everything (email, web, mysql, php, etc), but all sites are controlled by me and we don't allow access to cpanel/whm to anyone but me.

Question: Is Cpanel finally ready for a 64bit OS? I will likely have CentOs 5 installed. I have been told by more than one datacenter that they recommend 32bit with PAE kernel for Cpanel w/12GB support. They claim that is more stable. I know there have been 64bit problems with Cpanel and/or updates in the past, but I *thought* those had been worked out. Can I get an official response here or one from people with actual experience?

From what I understand, the limits of PAE kernel are some performance penalties for memory mapping (in addition to the 32bit vs 64 bit one), and programs can only each access 4GB at a time.. That's not a huge deal for most things, but it might be nice to have the option of allocating more than 4GB to mysql.

Thank you!
cPanel should function just fine under either setup with CentOS (yum 64 bit works fine, up2date 64 bit has issues). 64 bit will require more memory, and the binaries will be larger.
 

vissa

Well-Known Member
May 12, 2003
46
0
156
cPanel should function just fine under either setup with CentOS (yum 64 bit works fine, up2date 64 bit has issues). 64 bit will require more memory, and the binaries will be larger.
Thanks. When you run Cpanel's updates, will it use YUM or up2date (on Centos)? I know on RedHat it uses up2date.
 

rpmws

Well-Known Member
Aug 14, 2001
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back woods of NC, USA
Thanks. When you run Cpanel's updates, will it use YUM or up2date (on Centos)? I know on RedHat it uses up2date.
i think both redhat el5 and centos5 use yum now.
 

hekri

Well-Known Member
Oct 14, 2003
147
2
168
Hello i have new centos 5.2 relase i686 i386 but i see that system instal PAE kernel its ok for cPanel? In other centos 5.1 servers i see normal kernel without PAE.