Relevance of Processor Cache for Web Servers vs. Database Servers

[jubo]

I am looking to configure a web and a database server. I am thinking about going dual core for the database server to increase parallelism for the transactions. As for the web server, I am uncertain whether dual core and a large processor cache helps? Does it make sense to go for dual core high L2 cache, or should I save money by going with a high speed celeron/pentium 4?

Thanks

 

[zephyrprime]

Well, a large cache helps a lot for web servers because web server average IPC sucks but it depends on your particular site.

Specifically, is your site asp or php or java or coldfusion? Also, how much bandwidth are you serving?

Also, what database server software are you using? Some of the lower end products don't even support multithreading.

 

[jubo]

I am doing ruby on rails with an apache frontend. Bandwidth wise, not too much but the application logic is rather complex. As for database, mysql 5.0 .

 

[zephyrprime]

A lot of processor cache would be useful for such a web server if it handled a lot of traffic which it doesn't sound like it will. A lesser processor will probably be adequate. Be sure you set good/many hard drives for the DB server.

 

[jubo]

Thanks Zephyr. I am thinking about an opteron 144 for the web server and maybe an opteron 175 for the database. BTW, how do the raptor 36GB shape up for reliability? I used one in my desktop for the last few years, so no complaints there, but I am curious about 24/7 operation.

 

[eastvillager]

Don't buy the 36 GB raptors. They're ok from a reliability standpoint, but do not make any sense from a performance standpoint. If you want raptors, you need either the 75GB or 150GB models, with latest firmware, to show a significant improvement over similarly priced(with much larger capacity)7200RPM drives.

Processor cache isn't going to do much for you until you put a significant load on the box. If you do end up loading both boxes, I'd expect the webserver to benefit more than the database, but that is just a guesstimate based on typical useage patterns for webservers/databases.

 

[imported_Questar]

Databases can benefit from cache. Keyword of course is "can".

I'm not up to speed on mysql, does it support things like forced bind variable substitution, which can make multiple queries run out of the cpu cache?

 

[EatSpam]

Originally posted by: jubo
Thanks Zephyr. I am thinking about an opteron 144 for the web server and maybe an opteron 175 for the database. BTW, how do the raptor 36GB shape up for reliability? I used one in my desktop for the last few years, so no complaints there, but I am curious about 24/7 operation.

I have had several running for the past few years. No problems.