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"the SSD seems to more than compensate" that really depends. If you are using the server for a web app, disk IO should be minimized and CPU is more likely to be

"the SSD seems to more than compensate" that really depends. If you are using the server for a web app, disk IO should be minimized and CPU is more likely to be a bottleneck. This assertion largely depends on how well your database can cache its queries. For the web apps I host, I'd rather have CPU over faster disk IO.

akkartik 14y ago
Depends on the characteristics of the webapp, and how much I/O it needs per request. On the other hand multiple CPUs only matter if you have a ton of traffic. My side projects do not :) At least for hobbyists Digital Ocean is very compelling.
trustfundbaby 14y ago
Tbh, I actually moved for the RAM and not the SSD, but again if you're running stuff like Sphinx or Elasticsearch (search engines which have their entire index stored on disk and then read into memory as needed), then having an SSD helps. Also in the case where you're running with swap because you don't have enough memory, SSD comes in handy too, mysql is particularly badly behaved in this respect, it swaps too easily unless you load the entire db into memory by setting innodb_buffer_pool_size equal to the size of the db + a little bit. long story short, an SSD can help out quite a bit more than you seem to suggest.
- mrinterweb 14y ago
  If you are hitting swap often, you're doing it wrong. The second any machine I'm running is hitting swap I'm reconfiguring the machine or resizing the machine so that it does not hit swap. MySQL can be tuned to work with the memory you allocate to it such that it does not hit swap. With the doubled memory it will be easier to allocate for query cache hits. There are definitely some things where disk IO is important, but swapping should not be in that equation unless you have a problem. I prefer better CPUs and Memory to disk IO on servers usually. The database server is the only server I care about having decent IO, and Linode does have decent IO for non-ssd drives (a lot better than AWS).

akkartik 14y ago

Depends on the characteristics of the webapp, and how much I/O it needs per request. On the other hand multiple CPUs only matter if you have a ton of traffic. My side projects do not :) At least for hobbyists Digital Ocean is very compelling.

trustfundbaby 14y ago

Tbh, I actually moved for the RAM and not the SSD, but again if you're running stuff like Sphinx or Elasticsearch (search engines which have their entire index stored on disk and then read into memory as needed), then having an SSD helps. Also in the case where you're running with swap because you don't have enough memory, SSD comes in handy too, mysql is particularly badly behaved in this respect, it swaps too easily unless you load the entire db into memory by setting innodb_buffer_pool_size equal to the size of the db + a little bit. long story short, an SSD can help out quite a bit more than you seem to suggest.

mrinterweb 14y ago
If you are hitting swap often, you're doing it wrong. The second any machine I'm running is hitting swap I'm reconfiguring the machine or resizing the machine so that it does not hit swap. MySQL can be tuned to work with the memory you allocate to it such that it does not hit swap. With the doubled memory it will be easier to allocate for query cache hits. There are definitely some things where disk IO is important, but swapping should not be in that equation unless you have a problem. I prefer better CPUs and Memory to disk IO on servers usually. The database server is the only server I care about having decent IO, and Linode does have decent IO for non-ssd drives (a lot better than AWS).