Markus, On 9/20/06 1:09 AM, "Markus Schaber" <schabi@xxxxxxxxxxxx> wrote: > Do you think that adding some posix_fadvise() calls to the backend to > pre-fetch some blocks into the OS cache asynchroneously could improve > that situation? Nope - this requires true multi-threading of the I/O, there need to be multiple seek operations running simultaneously. The current executor blocks on each page request, waiting for the I/O to happen before requesting the next page. The OS can't predict what random page is to be requested next. We can implement multiple scanners (already present in MPP), or we could implement AIO and fire off a number of simultaneous I/O requests for fulfillment. - Luke
