Re: [Libguestfs] [PATCH 2/3] file: Support zero without ZERO_RANGE
On Thu, Aug 02, 2018 at 10:05:28PM +0300, Nir Soffer wrote:
File systems not supporting FALLOC_FL_ZERO_RANGE yet fall back to
manual
zeroing.
We can avoid this by combining two fallocate calls:
fallocate(FALLOC_FL_PUNHCH_HOLE)
"PUNCH"
fallocate(0)
+#ifdef FALLOC_FL_PUNCH_HOLE
+ /* If we can punch hole but may not trim, we can combine punching hole and
+ fallocate to zero a range. This is expected to be more efficient than
+ writing zeros manually. */
Although we can fix this before pushing so there's no need to submit a
new version, it's better if the comment style sticks to the same as
used elsewhere, ie:
/* Commmnt
* More comment
*/
Rich.
--
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