c/mirror_zfs
1
0
Fork 0
mirror of https://git.proxmox.com/git/mirror_zfs.git synced 2026-03-10 20:36:21 +03:00
Code Issues Packages Projects Releases Wiki Activity

zdb: adjust block histogram binning strategy

Browse Source 
Previously, a bin included all blocks _starting_ from given size
(e.g., a "4K" bin would include all blocks within the [4K; 8K) region).
This is counter-intuitive and does not match the typical use-case of the
block histogram (that is, to estimate disk usage considering how ZFS'
block allocation works). In other words, if I'm looking at the "4K" row,
I'm interested in records that _fit into_ a 4K block.

Adjust the binning strategy such that a bin includes all blocks _up to_
given size, such that e.g. a "4K" bin would include all blocks within
the (2K; 4K] region.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ivan Shapovalov <intelfx@intelfx.name>
Closes #16999
This commit is contained in:
Ivan Shapovalov 2024-12-10 19:58:35 +04:00 committed by Brian Behlendorf
parent 3a1a22abb4
commit f8b082b5af
1 changed files with 6 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
cmd/zdb/zdb.c
View File

@ -6254,7 +6254,12 @@ skipped:
*/
int bin;
#define BIN(size) (highbit64(size) - 1)
/*
* Binning strategy: each bin includes blocks up to and including
* the given size (excluding blocks that fit into the previous bin).
* This way, the "4K" bin includes blocks within the (2K; 4K] range.
*/
#define BIN(size) (highbit64((size) - 1))
switch (block_bin_mode) {
case BIN_PSIZE: bin = BIN(BP_GET_PSIZE(bp)); break;