On 11/6/19 10:53 PM, Jan Kara wrote:
On Wed 16-10-19 13:07:06, Ritesh Harjani wrote:
This patch series adds the support for blocksize < pagesize for
dioread_nolock feature.
Since in case of blocksize < pagesize, we can have multiple
small buffers of page as unwritten extents, we need to
maintain a vector of these unwritten extents which needs
the conversion after the IO is complete. Thus, we maintain
a list of tuple <offset, size> pair (io_end_vec) for this &
traverse this list to do the unwritten to written conversion.
Appreciate any reviews/comments on this patches.
I know Ted has merged the patches already so this is just informational but
I've read the patches and they look fine to me. Thanks for the work! I was
Appreciate your help too for valuable feedback & pointers at various places.
just thinking that we could actually make the vector tracking more
efficient because the io_end always looks like:
one-big-extent-to-fully-write + whatever it takes to fully write out the
last page
So your vectors could be also expressed as "extent to write" + bitmap of
blocks written in the last page. And 64-bits are enough for the bitmap for
anything ext4 supports so we could easily save allocation of ioend_vec etc.
Just a suggestion.
Yes, sounds good to me. Although slab allocations are also fast.
However I agree this should be more efficient and will also avoid the
list management and or list pointer traversal.
Sure, will work over this optimization once I get some closure on some
ongoing open items.
Thanks & appreciate your feedback.
ritesh
