Re: Hard disk speed - Maybe OT

Bob Bob wrote:
[...]
I dont think RAM will help all that much. The actual I/O rate numbers look like;

RAM always helps. More RAM = more buffer. Without RAM the data has to be written to disk sooner, and that's slow. Btw, the fact that swap is used at all on a machine that is not multi-user means it's time to get more RAM. The machine should never use swap at all. If you really can't add more RAM, you should move the swap partition to a hard drive that isn't used much. Using swap results in disk thrashing and disk I/O suffers (greatly).


as the capture rate. hdparm -tT for one of the RAID0 devices shows about 20Mbytes/sec buffered disk reads. Maybe there is a lot more I/O going on than I thought?

If you really have millions of files, it is crucial to not have more than 700.000 per directory. Google for "reiserfs millions of files".

But again, more RAM (another 256MB wouldn't hurt) and a faster disk (access time is more important here than throughput) will help. And RAM is cheap these days, so why not just try.
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