[CentOS] Piranha vs HAProxy vs Something else

[Christopher Chan]

Les Mikesell wrote:
> Christopher Chan wrote:
>>
>> Haha. Yes, I know that more and more appliances are getting Linux 
>> based control systems but I am certainly very interested in how they 
>> got a box running a 2.4 version of Linux to perform like what I saw. I 
>> had upgraded the mailservers of the company to get a bit more 
>> performance by moving to 2.6 but F5 runs a 2.4.x Linux kernel and has 
>> a single box perform better than a cluster of the mailservers I 
>> upgraded to 2.6?!
>>
>> What do they have in those boxes? ASICs doing smtp and dns that 
>> somehow create zero network latency? What patches do they have in 
>> their souped up sccp version?
> 
> F5 is known more for load balancing than mail servers so I'm not sure 
> what you saw, but if you were throwing hardware at mail server 
> performance the first thing to add would be battery-backed RAM on the 
> disk/raid controllers so you don't have to wait for disk head motion to 
> complete when the mail application fsync's each write.
> 

Okay, so those mailservers in the cluster did not have 3ware 955x 
controllers. In fact, they use linux md. There was one box that did have 
such a controller and had BBU cache RAM (10 disks attached in RAID5 
mode). That box still did not do anything near what the F5 box did. One 
of the F5 guys did say that the cache of the RAID controller of the F5 
box was involved in the mail queue guarantee but he also said something 
about the filesystem layer being bypassed...ah well.