On 01/10/2014 12:32 PM, Josh Boyer wrote: > On Thu, Jan 9, 2014 at 5:28 PM, Karanbir Singh <mail-lists at karan.org> wrote: >> On 01/09/2014 02:22 PM, Josh Boyer wrote: >>> OK, but it's still a kernel based on the RHEL kernel, just with the >>> changes/additions backported to it. It isn't a bump to e.g. the Linux >>> 3.10 stable release or something. Correct? >> >> the xen4centos kernel is mainline based 3.x > > Interesting. I'll have a look. Do you know or have pointers to why > they chose to go that route? > We tried, quite a bit, to try and get the xen stuff backported into the 2.6.32-EL6 kernel, but given the patch overlap was something we cant control and lack the time and technical depth in kernel code to maintain that longer term ( this was essentially Johnny and me, doing this over and above most other things ), it was just easier to go down that route. Secondly, there are quite a few anecdotal pieces on dramatic performance improvements in newer kernels, I know atleast one of the top 5 CDN's ( ie carry > 25Gibt/sec ) that recently switched over from the distro centos kernel to a inhouse 3.10 build for 'network perforamnce'. In quotes, because repeated questions and pokes in various media have failed to get a reasonable, tangiable, technical response out of them beyond 'network perforamance'. - KB -- Karanbir Singh +44-207-0999389 | http://www.karan.org/ | twitter.com/kbsingh GnuPG Key : http://www.karan.org/publickey.asc