-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Fred Williams wrote: > Have you ever actually used a version of Windows?
Windows 1.0 (once), Windows 2/286, Windows 3, 3.1, 3.11, 95, 98, ME, 2000, XP, 2003 and Vista. > ANY OS that attempts to read in a xGigibyte file into real memory to the > detriment of the entire system load is not working correctly. Call it a bug > or a feature it still sucks. If the other tasks aren't doing anything then it slows down the reading task by not using using as much memory as is reasonable. For example not using half the RAM for the file caching just in case a background task may came to life in the future will slow down the file task which then increases the probability that a background task will be needed. Getting this stuff right is not easy. The kernel cannot predict the future and instead has to use heuristics which involve tradeoffs of throughput against latency. There will always be cases where the heuristics get it wrong, but the goal is to get it right the vast majority of the time. Linux has exactly the same issue. Ultimately a kernel variable named swappiness is used with a default value, but is administrator adjustable because even they couldn't work a single correct value for every situation. http://lwn.net/Articles/83588/ Everyone recognises the degenerate cases are bad, but even then it is questionable. Do you want the file task to take 1 minute and then have all your other tasks take 10 seconds to become fully responsive, or do you want your file task to take 5 minutes while your other tasks are mostly responsive? If you have some algorithm, parameters and heuristics that work under all workloads and configurations then I am sure the operating systems community would love to hear from you. Roger -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFI0Y/lmOOfHg372QQRAlMbAKCB3acOdcnIw2JRIGrrOh//jw/0rgCdG2AQ SvyDyo3K3fsxtxhYgsAGVeU= =X+SR -----END PGP SIGNATURE----- _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
