On Thu, 19 Nov 2009, Greg Smith wrote:
This is why turning the cache off can tank performance so badly--you're going to be writing a whole 128K block no matter what if it's force to disk without caching, even if it's just to write a 8K page to it.
Theoretically, this does not need to be the case. Now, I don't know what the Intel drives actually do, but remember that for flash, it is the *erase* cycle that has to be done in large blocks. Writing itself can be done in small blocks, to previously erased sites.
The technology for combining small writes into sequential writes has been around for 17 years or so in http://portal.acm.org/citation.cfm?id=146943&dl= so there really isn't any excuse for modern flash drives not giving really fast small writes.
Matthew -- for a in past present future; do for b in clients employers associates relatives neighbours pets; do echo "The opinions here in no way reflect the opinions of my $a $b." done; done -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
