Ian Lance Taylor <[EMAIL PROTECTED]> writes: > (Actually, though, Postgres is already vulnerable to erratic behaviour > because any backend process can corrupt the shared buffer pool.)
Not to mention the other parts of shared memory. Nonetheless, our experience has been that cross-backend failures due to memory clobbers in shared memory are very infrequent --- certainly far less often than we see localized-to-a-backend crashes. Probably this is because the shared memory is (a) small compared to the rest of the address space and (b) only accessed by certain specific modules within Postgres. I'm convinced that switching to a thread model would result in a significant degradation in our ability to recover from coredump-type failures, even given the (implausible) assumption that we introduce no new bugs during the conversion. I'm also *un*convinced that such a conversion will yield significant performance benefits, unless we introduce additional cross-thread dependencies (and more fragility and lock contention) by tactics such as sharing catalog caches across threads. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly