mirror_zfs/lib/libuutil
Rob Norris 3e7e19e028 pool_iter_refresh: don't refresh pools twice
In "all pools" mode, pool_iter_refresh() will call zpool_iter(), which
will call zpool_refresh_stats() before calling add_pool(). If we already
have the pool, this is a different handle, so we just release it and
return. Back in pool_iter_refresh(), we then call zpool_stats_refresh()
again for our handle on the same pool.

All together, this means we're doing two ZFS_IOC_POOL_STATS calls into
the kernel for every pool in the system. This isn't wrong, but it does
double the pressure on global locks.

Instead, we add a new function zpool_refresh_stats_from_handle() that
simply copies the pool config and state from one handle to another, and
use it to update our handle before we release it in add_pool(), so we
only have one call per pool per interval.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #17807
2025-10-21 09:50:43 -07:00
..
libuutil.abi pool_iter_refresh: don't refresh pools twice 2025-10-21 09:50:43 -07:00
libuutil.suppr Library ABI tracking with abigail 2020-11-17 09:18:52 -08:00
Makefile.am Cleanup: Remove unused uu_pname code 2022-09-19 17:33:52 -07:00
uu_alloc.c SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
uu_avl.c SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
uu_ident.c SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
uu_list.c SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
uu_misc.c SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
uu_string.c SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00