mirror_zfs/module/zfs/ddt_stats.c
Rob Norris 27e9cb5f80 ddt: cleanup the stats & histogram code
Both the API and the code were kinda mangled and I was really struggling
to follow it. The worst offender was the old ddt_stat_add(); after
fixing it up the rest of the changes are mostly knock-on effects and
targets of opportunity.

Note that the old ddt_stat_add() was safe against overflows - it could
produce crazy numbers, but the compiler wouldn't do anything stupid. The
assertions in ddt_stat_sub() go a lot of the way to protecting against
this; getting in a position where overflows are a problem is definitely
a programming error.

Also expanding ddt_stat_add() and ddt_histogram_empty() produces less
efficient assembly. I'm not bothered about this right now though; these
should not be hot functions, and if they are we'll optimise them later.
If we have to go back to the old form, we'll comment it like crazy.

Finally, I've removed the assertion that the bucket will never be
negative, as it will soon be possible to have entries with zero
refcounts: an entry for a block that is no longer on the pool, but is on
the log waiting to be synced out. It might be better to have a separate
bucket for these, since they're still using real space on disk, but
ultimately these stats are driving UI, and for now I've chosen to keep
them matching how they've looked in the past, as well as match the
operators mental model - pool usage is managed elsewhere.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: iXsystems, Inc.
Closes #15895
2024-08-16 12:02:56 -07:00

332 lines
8.1 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or https://opensource.org/licenses/CDDL-1.0.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2016 by Delphix. All rights reserved.
* Copyright (c) 2022 by Pawel Jakub Dawidek
* Copyright (c) 2023, Klara Inc.
*/
#include <sys/zfs_context.h>
#include <sys/spa.h>
#include <sys/spa_impl.h>
#include <sys/ddt.h>
#include <sys/ddt_impl.h>
static void
ddt_stat_generate(ddt_t *ddt, const ddt_lightweight_entry_t *ddlwe,
ddt_stat_t *dds)
{
spa_t *spa = ddt->ddt_spa;
uint64_t lsize = DDK_GET_LSIZE(&ddlwe->ddlwe_key);
uint64_t psize = DDK_GET_PSIZE(&ddlwe->ddlwe_key);
memset(dds, 0, sizeof (*dds));
for (int p = 0; p < ddlwe->ddlwe_nphys; p++) {
const ddt_univ_phys_t *ddp = &ddlwe->ddlwe_phys;
ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p);
if (ddt_phys_birth(ddp, v) == 0)
continue;
int ndvas = ddt_phys_dva_count(ddp, v,
DDK_GET_CRYPT(&ddlwe->ddlwe_key));
const dva_t *dvas = (ddt->ddt_flags & DDT_FLAG_FLAT) ?
ddp->ddp_flat.ddp_dva : ddp->ddp_trad[p].ddp_dva;
uint64_t dsize = 0;
for (int d = 0; d < ndvas; d++)
dsize += dva_get_dsize_sync(spa, &dvas[d]);
uint64_t refcnt = ddt_phys_refcnt(ddp, v);
dds->dds_blocks += 1;
dds->dds_lsize += lsize;
dds->dds_psize += psize;
dds->dds_dsize += dsize;
dds->dds_ref_blocks += refcnt;
dds->dds_ref_lsize += lsize * refcnt;
dds->dds_ref_psize += psize * refcnt;
dds->dds_ref_dsize += dsize * refcnt;
}
}
static void
ddt_stat_add(ddt_stat_t *dst, const ddt_stat_t *src)
{
dst->dds_blocks += src->dds_blocks;
dst->dds_lsize += src->dds_lsize;
dst->dds_psize += src->dds_psize;
dst->dds_dsize += src->dds_dsize;
dst->dds_ref_blocks += src->dds_ref_blocks;
dst->dds_ref_lsize += src->dds_ref_lsize;
dst->dds_ref_psize += src->dds_ref_psize;
dst->dds_ref_dsize += src->dds_ref_dsize;
}
static void
ddt_stat_sub(ddt_stat_t *dst, const ddt_stat_t *src)
{
/* This caught more during development than you might expect... */
ASSERT3U(dst->dds_blocks, >=, src->dds_blocks);
ASSERT3U(dst->dds_lsize, >=, src->dds_lsize);
ASSERT3U(dst->dds_psize, >=, src->dds_psize);
ASSERT3U(dst->dds_dsize, >=, src->dds_dsize);
ASSERT3U(dst->dds_ref_blocks, >=, src->dds_ref_blocks);
ASSERT3U(dst->dds_ref_lsize, >=, src->dds_ref_lsize);
ASSERT3U(dst->dds_ref_psize, >=, src->dds_ref_psize);
ASSERT3U(dst->dds_ref_dsize, >=, src->dds_ref_dsize);
dst->dds_blocks -= src->dds_blocks;
dst->dds_lsize -= src->dds_lsize;
dst->dds_psize -= src->dds_psize;
dst->dds_dsize -= src->dds_dsize;
dst->dds_ref_blocks -= src->dds_ref_blocks;
dst->dds_ref_lsize -= src->dds_ref_lsize;
dst->dds_ref_psize -= src->dds_ref_psize;
dst->dds_ref_dsize -= src->dds_ref_dsize;
}
void
ddt_histogram_add_entry(ddt_t *ddt, ddt_histogram_t *ddh,
const ddt_lightweight_entry_t *ddlwe)
{
ddt_stat_t dds;
int bucket;
ddt_stat_generate(ddt, ddlwe, &dds);
bucket = highbit64(dds.dds_ref_blocks) - 1;
if (bucket < 0)
return;
ddt_stat_add(&ddh->ddh_stat[bucket], &dds);
}
void
ddt_histogram_sub_entry(ddt_t *ddt, ddt_histogram_t *ddh,
const ddt_lightweight_entry_t *ddlwe)
{
ddt_stat_t dds;
int bucket;
ddt_stat_generate(ddt, ddlwe, &dds);
bucket = highbit64(dds.dds_ref_blocks) - 1;
if (bucket < 0)
return;
ddt_stat_sub(&ddh->ddh_stat[bucket], &dds);
}
void
ddt_histogram_add(ddt_histogram_t *dst, const ddt_histogram_t *src)
{
for (int h = 0; h < 64; h++)
ddt_stat_add(&dst->ddh_stat[h], &src->ddh_stat[h]);
}
void
ddt_histogram_total(ddt_stat_t *dds, const ddt_histogram_t *ddh)
{
memset(dds, 0, sizeof (*dds));
for (int h = 0; h < 64; h++)
ddt_stat_add(dds, &ddh->ddh_stat[h]);
}
boolean_t
ddt_histogram_empty(const ddt_histogram_t *ddh)
{
for (int h = 0; h < 64; h++) {
const ddt_stat_t *dds = &ddh->ddh_stat[h];
if (dds->dds_blocks == 0 &&
dds->dds_lsize == 0 &&
dds->dds_psize == 0 &&
dds->dds_dsize == 0 &&
dds->dds_ref_blocks == 0 &&
dds->dds_ref_lsize == 0 &&
dds->dds_ref_psize == 0 &&
dds->dds_ref_dsize == 0)
continue;
return (B_FALSE);
}
return (B_TRUE);
}
void
ddt_get_dedup_object_stats(spa_t *spa, ddt_object_t *ddo_total)
{
memset(ddo_total, 0, sizeof (*ddo_total));
for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
ddt_t *ddt = spa->spa_ddt[c];
if (!ddt)
continue;
for (ddt_type_t type = 0; type < DDT_TYPES; type++) {
for (ddt_class_t class = 0; class < DDT_CLASSES;
class++) {
dmu_object_info_t doi;
uint64_t cnt;
int err;
/*
* These stats were originally calculated
* during ddt_object_load().
*/
err = ddt_object_info(ddt, type, class, &doi);
if (err != 0)
continue;
err = ddt_object_count(ddt, type, class, &cnt);
if (err != 0)
continue;
ddt_object_t *ddo =
&ddt->ddt_object_stats[type][class];
ddo->ddo_count = cnt;
ddo->ddo_dspace =
doi.doi_physical_blocks_512 << 9;
ddo->ddo_mspace = doi.doi_fill_count *
doi.doi_data_block_size;
ddo_total->ddo_count += ddo->ddo_count;
ddo_total->ddo_dspace += ddo->ddo_dspace;
ddo_total->ddo_mspace += ddo->ddo_mspace;
}
}
}
/*
* This returns raw counts (not averages). One of the consumers,
* print_dedup_stats(), historically has expected raw counts.
*/
spa->spa_dedup_dsize = ddo_total->ddo_dspace;
}
uint64_t
ddt_get_ddt_dsize(spa_t *spa)
{
ddt_object_t ddo_total;
/* recalculate after each txg sync */
if (spa->spa_dedup_dsize == ~0ULL)
ddt_get_dedup_object_stats(spa, &ddo_total);
return (spa->spa_dedup_dsize);
}
void
ddt_get_dedup_histogram(spa_t *spa, ddt_histogram_t *ddh)
{
for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
ddt_t *ddt = spa->spa_ddt[c];
if (!ddt)
continue;
for (ddt_type_t type = 0; type < DDT_TYPES; type++) {
for (ddt_class_t class = 0; class < DDT_CLASSES;
class++) {
ddt_histogram_add(ddh,
&ddt->ddt_histogram_cache[type][class]);
}
}
}
}
void
ddt_get_dedup_stats(spa_t *spa, ddt_stat_t *dds_total)
{
ddt_histogram_t *ddh_total;
ddh_total = kmem_zalloc(sizeof (ddt_histogram_t), KM_SLEEP);
ddt_get_dedup_histogram(spa, ddh_total);
ddt_histogram_total(dds_total, ddh_total);
kmem_free(ddh_total, sizeof (ddt_histogram_t));
}
uint64_t
ddt_get_dedup_dspace(spa_t *spa)
{
ddt_stat_t dds_total;
if (spa->spa_dedup_dspace != ~0ULL)
return (spa->spa_dedup_dspace);
memset(&dds_total, 0, sizeof (ddt_stat_t));
/* Calculate and cache the stats */
ddt_get_dedup_stats(spa, &dds_total);
spa->spa_dedup_dspace = dds_total.dds_ref_dsize - dds_total.dds_dsize;
return (spa->spa_dedup_dspace);
}
uint64_t
ddt_get_pool_dedup_ratio(spa_t *spa)
{
ddt_stat_t dds_total = { 0 };
ddt_get_dedup_stats(spa, &dds_total);
if (dds_total.dds_dsize == 0)
return (100);
return (dds_total.dds_ref_dsize * 100 / dds_total.dds_dsize);
}
int
ddt_get_pool_dedup_cached(spa_t *spa, uint64_t *psize)
{
uint64_t l1sz, l1tot, l2sz, l2tot;
int err = 0;
l1tot = l2tot = 0;
*psize = 0;
for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
ddt_t *ddt = spa->spa_ddt[c];
if (ddt == NULL)
continue;
for (ddt_type_t type = 0; type < DDT_TYPES; type++) {
for (ddt_class_t class = 0; class < DDT_CLASSES;
class++) {
err = dmu_object_cached_size(ddt->ddt_os,
ddt->ddt_object[type][class], &l1sz, &l2sz);
if (err != 0)
return (err);
l1tot += l1sz;
l2tot += l2sz;
}
}
}
*psize = l1tot + l2tot;
return (err);
}