SPARC T1 Technology and Messaging Server Architecture

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This FAQ has been moved to Oracle's Unified Communications Suite wiki space here: http://wikis.sun.com/display/CommSuite/SPARC+T1+Technology+and+Messaging+Server+Architecture

Given a choice, what are the optimal components on which one should deploy SPARC T1 technology in a messaging architecture: master/consumer LDAP, MMP, MTA, Message Store?

Customer Response 1:

• LDAP (master/consumer): The best machines seem to be the Sun x86 boxes - x2200, x4100, x4200, x4600.
• MMP: Other folks may have different opinions on this, but given how the MMP is not heavily multi-threaded, a high cpu clock rate, few CPUs, like a x2200 seems ideal.
• MTA: A T1 might do well here, but these are far more bounded by IO than CPU. Again, mid-sized x86 servers like x4100, x4200 are probably the best.
• Message Store: Here's where the T1's probably would do the best, given the highly multi-threaded nature of the store.

Sun Response 1:

• One thing to throw into the mix: spam and virus scanning. For example, the MTA itself is indeed I/O bound and not CPU bound. (And hence why we would always wonder when we'd learn of a customer running the MTA on a 10K.) However, at sites with significant amounts of inbound mail, all needing scanning, the real bottleneck for the Internet facing MTAs is waiting on verdicts from the scanners. It's not at all unusual to see deployments with more iron for the scanners than the inbound MTAs themselves. The typical numbers I hear these days is that spam is 90%+ of the inbound mail. So to get back on topic, the choice of hardware to run the scanners on is also an important consideration.

Customer Response 2:

• LDAP (master/consumer): The best machines seem to be the Sun x86 boxes - x2200, x4100, x4200, x4600. You could of course substitute the v490 here. Very good single thread performance which with the latest systems seems to perform comparably to Opteron. (Although at ~twice the cost factor). Sparc IV+ is a very nice chip indeed and the 32 MB level 3 cache is certainly what helps it out significantly.

I have just recently moved two 5.2 directory servers from v480 -> T2000 ->v490. Why? The T2000's performed very well in read operations and the ability to handle many simultaneous large queries was very good indeed. Where 'we' had a problem was with our own batch processes that run overnight and 'touch' objects in the directory. We have around 250K object count and the directory server as far as I am aware only has one thread allocated to writes (which seems logical). On the the T2000 this became a major bottleneck for us as our batch process was becoming a major issue time wise, more so than LDAP performance through the day. (Ideally we would touch this data and outside the directory and then bulk load, but that is another story ;)) We split the batch every which way and still only managed to get v480 performance level. Being that the cores of a v480 at 1GHz and a T2000 at 1GHz are basically very similar the results showed quite clearly the LDAP directory IO blocking on a single thread.) On the T2000, I managed to drive these things to extremely high numbers of simultaneous large queries with very good results. If you are only using these systems as a read only type directory (not a an attempt at a directory / relational database like us :)) then they have a very good price performance. (4 DDR2 memory controllers on chip makes for great memory bandwidth) So back to your original question. The T2000 would make an excellent consumer LDAP server. a bit dubious as a master in my opinion.

• MMP: Other folks may have different opinions on this, but given how the MMP is not heavily multi-threaded, a high cpu clock rate, few CPUs, like a x2200 seems ideal. Or v210,240,440 or 215,245,445 like we use. Pretty similar price wise. Opteron has the edge in performance. SPARC has the edge in system reliability probably.
• MTA: A T1 might do well here, but these are far more bounded by IO than CPU. Again, mid-sized x86 servers like x4100, x4200 are probably the best. Could be interesting top try the T2000 here I would imagine... I would like to see a comparison here. Personally I use Opterons here... (X4200's). Most resources on these systems goes into Spam Assassin for tagging messages.
• Message Store: Here's where the T1's probably would do the best, given the highly multi-threaded nature of the store. Agreed. We use v440's which seem to work pretty well for our workload.

Customer Response 3:

• MTA: We don't actually run the Sun MTAs on our Internet facing machines but we have switched to T2000s. We run exim with mailscanner and spamassassin and found that something like 6-7 decent v240s could easily be replaced with a single T2000. For jobs like this, the T1 is excellent (and uses the power of less than two of the machines they replace). Disk IO to the internal disks sucks though so beware of that. Also, beware of SSL traps - they are dog slow at SSL unless you use the sun openssl libs or build your own with the pkcs11 patch. Overall, they are nice machines. Would like a bigger one with some real disks instead of the little SAS things though

Customer Response 4:

• Interesting, we use Exim and Spam Assassin on x4200's. Again around 3 times the performance of the v240's here... (Exim is something I picked up when I lived in the UK and when I was Systems Manager at SGHMS ;))
• Agreed on the disk IO. One thing I have found useful here with my X4200's (being as they are the same form factor as a T2000) is to use ZFS as the mail spool volume and it makes these things really fly when it comes to shifting mail. On closer inspection one sees ZFS taking up all available memory in caching which seems to boost performance of these as an inward MTA/ Spam tagging appliance.(Which is what I use them for.)