Re: Bottlenecks

Mxsmanic pravi:
If you got enough cache, the prefetching and caching will zero out the access time in most situations. What kind of cases are we talking about?

For random access to large databases, cache is essentially useless;
every access to the database will generate physical disk I/O.

Yes, but not in a time-dependent fashion. A write to the cache will not make the application wait for the actual write to be made. Rather, the data will go into the cache and the cache will independently write it to the disk. Unless you are persistently writing in very different locations of a very large database, a cache of 1 GB will pretty much provide sufficient buffer space for your writing needs. The cache will also allow for optimizations in writing (cache has 0 seek time, disk has enormous seek time).


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