From: Frediano Ziglio <frediano.ziglio@citrix.com>

Reduce some number of parts passed to writev.
Avoid possible allocation sending data with writev.
Reduce number of allocations sending memory state.

Changes since v1:
- add commit to cache up to 4 pages in hypercall;
- add other 2 commits reducing chunks passed to write/writev.

Edwin Török (2):
  tools/libs/guest: allocate various migration arrays just once
  tools/lib/call: cache up to 4 pages in hypercall bounce buffers

Frediano Ziglio (5):
  xenguest: Reduce number of parts in write_split_record
  xenguest: Reduce number of I/O vectors in write_batch
  xenguest: Allows writev_exact to change iov array
  xenguest: Reduce number of I/O vectors in write_batch
  xenguest: Use a single write_exact in write_headers

 tools/libs/call/buffer.c        |  28 +++---
 tools/libs/call/core.c          |   3 +-
 tools/libs/call/private.h       |   8 +-
 tools/libs/ctrl/xc_private.c    |  26 ++----
 tools/libs/ctrl/xc_private.h    |   2 +-
 tools/libs/guest/xg_sr_common.c |   6 +-
 tools/libs/guest/xg_sr_common.h |  13 +++
 tools/libs/guest/xg_sr_save.c   | 147 +++++++++++++++-----------------
 8 files changed, 114 insertions(+), 119 deletions(-)

-- 
2.53.0

On Mon, Apr 27, 2026 at 11:53:25AM +0100, Frediano Ziglio wrote:
> Edwin Török (2):
>   tools/libs/guest: allocate various migration arrays just once
>   tools/lib/call: cache up to 4 pages in hypercall bounce buffers
> 
> Frediano Ziglio (5):
>   xenguest: Reduce number of parts in write_split_record
>   xenguest: Reduce number of I/O vectors in write_batch
>   xenguest: Allows writev_exact to change iov array
>   xenguest: Reduce number of I/O vectors in write_batch
>   xenguest: Use a single write_exact in write_headers

Hi Frediano,

When you will resend the patch, could you change the prefix? "xenguest"
to me is a XenServer / XCP-ng binary that happen to live in the xen
repo, not something that exist upstream. There's plenty of better way to
prefix those commits, looking at the history of the lib:
    libs/guest
    libs/xg
    tools/libs/guest
    tools/xg
    tools/libxg
    tools/libs/guest

I think I prefer "libs/guest".

And looks like there's one patch that doesn't touch libxenguest at all,
yet it is prefix with "xenguest:".

Cheers,


-- 
Anthony Perard | Vates XCP-ng Developer

XCP-ng & Xen Orchestra - Vates solutions

web: https://vates.tech