Messages in this thread | | | From | "Albert D. Cahalan" <> | Subject | Re: [patch 6/12] hold atomic kmaps across generic_file_read | Date | Sun, 11 Aug 2002 20:18:14 -0400 (EDT) |
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Jeff Garzik writes: > Linus Torvalds wrote:
> The overhead of the extra stat and mmap/munmap syscalls seemed to be the > thing that slowed things down. sendfile was pretty fast, but still an > extra syscall, with an annoyingly large error handling case [only > certain files can be sendfile'd]
That error handling case sure does discourage sendfile use.
> I sure would like an O_STREAMING flag, though... let a user app hint to > the system that the pages it is reading or writing are perhaps less > likely to be reused, or access randomly.... A copy-file syscall would > be nice, too, but that's just laziness talking....
You have a laptop computer with a USB-connected Ethernet. You mount a NetApp or similar box via the SMB/CIFS protocol. You see a multi-gigabyte file. You make a copy... ouch!!! For each gigabyte, you hog the network for an hour.
Now let's say this file is for a MacOS app. You have to preserve the creator, file type, resource fork, etc. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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