Messages in this thread | | | Subject | Re: [PATCH][RFC] fast file mapping for loop | From | Andi Kleen <> | Date | Wed, 09 Jan 2008 16:34:23 +0100 |
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Jens Axboe <jens.axboe@oracle.com> writes: > > So how does it work? Instead of punting IO to a thread and passing it > through the page cache, we instead attempt to send the IO directly to the
Great -- something like this was needed for a long time.
> - The file block mappings must not change while loop is using the file. > This means that we have to ensure exclusive access to the file and > this is the bit that is currently missing in the implementation. It > would be nice if we could just do this via open(), ideas welcome...
get_write_access()/put_write_access() will block other writers.
But as pointed out by others that is not enough for this.
I suppose you could use a white list like a special flag for file systems (like ext2/ext3) that do not reallocate blocks.
-Andi
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