Messages in this thread | | | Date | Thu, 13 Apr 2006 16:08:43 +0200 (MEST) | From | Jan Engelhardt <> | Subject | Re: What is the most efficient way to copy a bunch of files nowadays? |
| |
>After having read-only mucked with the headers of a bunch of files[1] >I've selected a subset of 2500 or so with sizes going from 2K to 85M >which I want to copy to another directory in the same local >filesystem. What is the "best" (
>CPU usage
nice
>fragmentation
What? You can't really influence it.
>wall clock time
Using a filesystem with aggressive caching.
>system responsiveness during and after the copy)
See one above. Set /proc/sys/vm/dirty_ratio high to have the flush taking place late, or low to have it "early+often".
>way to copy these files? read+write, mmap+write, read+mmap, >mmap+mmap+memcpy,
It all boils down to the same: read the file and write it back. So all your methods cost equally much. With splice() instead of read/write however, you may save some cycles.
>something else? That's with recent kernels, of course.
Jan Engelhardt -- - 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/
| |