| Message ID | 20241106192105.6731-1-kanchana.p.sridhar@intel.com |
|---|---|
| Headers | show |
| Series | zswap IAA compress batching | expand |
On Wed, 6 Nov 2024 11:20:52 -0800 Kanchana P Sridhar <kanchana.p.sridhar@intel.com> wrote:
> IAA Compression Batching:
hm, is this a crypto patchset or a zswap patchset?
Thanks. Unless someone stops me I think I'll add this to mm.git after
6.13-rc1 is released. To get it additional testing exposure while
review proceeds.
> -----Original Message----- > From: Andrew Morton <akpm@linux-foundation.org> > Sent: Wednesday, November 6, 2024 12:26 PM > To: Sridhar, Kanchana P <kanchana.p.sridhar@intel.com> > Cc: linux-kernel@vger.kernel.org; linux-mm@kvack.org; > hannes@cmpxchg.org; yosryahmed@google.com; nphamcs@gmail.com; > chengming.zhou@linux.dev; usamaarif642@gmail.com; > ryan.roberts@arm.com; Huang, Ying <ying.huang@intel.com>; > 21cnbao@gmail.com; linux-crypto@vger.kernel.org; > herbert@gondor.apana.org.au; davem@davemloft.net; > clabbe@baylibre.com; ardb@kernel.org; ebiggers@google.com; > surenb@google.com; Accardi, Kristen C <kristen.c.accardi@intel.com>; > zanussi@kernel.org; Feghali, Wajdi K <wajdi.k.feghali@intel.com>; Gopal, > Vinodh <vinodh.gopal@intel.com> > Subject: Re: [PATCH v3 00/13] zswap IAA compress batching > > On Wed, 6 Nov 2024 11:20:52 -0800 Kanchana P Sridhar > <kanchana.p.sridhar@intel.com> wrote: > > > IAA Compression Batching: > > hm, is this a crypto patchset or a zswap patchset? Thanks Andrew, for this observation. Since this patch-series attempts to improve zswap_store() latency for large folios using Intel IAA hardware acceleration, it has patches in crypto and in zswap, to make it easier for the reviewers to understand context. I am Ok with organizing the patch-series differently if that makes better sense. Appreciate suggestions with regards to this. Thanks, Kanchana > > Thanks. Unless someone stops me I think I'll add this to mm.git after > 6.13-rc1 is released. To get it additional testing exposure while > review proceeds.
IAA Compression Batching: ========================= This patch-series introduces the use of the Intel Analytics Accelerator (IAA) for parallel compression of pages in large folios. The patch-series is organized as follows: 1) crypto acomp & iaa_crypto driver enablers for batching: Relevant patches are tagged with "crypto:" in the subject: Patch 1) New acomp_alg/crypto_acomp batch_compress() and batch_decompress() interfaces, that swap modules can invoke using the new batching API crypto_acomp_batch_compress() and crypto_acomp_batch_decompress(). Patch 2) New CRYPTO_ACOMP_REQ_POLL acomp_req flag to act as a gate for async poll mode in iaa_crypto. Patch 3) iaa-crypto driver implementations for async polling, crypto_acomp_batch_compress() and crypto_acomp_batch_decompress(). Patch 4) Modifying the default iaa_crypto driver mode to async. Patch 5) Disabling verify_compress by default, to facilitate users to run IAA easily for comparison with software compressors. Patch 6) Changing the cpu-to-iaa mappings to more evenly balance cores to IAA devices. Patch 7) Addition of a "global_wq" per IAA, which can be used as a global resource for compress jobs for the socket. If the user configures 2WQs per IAA device, the driver will distribute compress jobs from all cores on the socket to the "global_wqs" of all the IAA devices on that socket, in a round-robin manner. This can be used to improve compression throughput for workloads that see a lot of swapout activity. 2) zswap modifications to enable compress batching in zswap_store() of large folios (including pmd-mappable folios): Patch 8) acomp_ctx mutex lock acquire/release once optimizations in zswap_store() and a minor change in releasing the lock in zswap_decompress(). Patch 9) Change the "struct crypto_acomp_ctx" to contain a configurable number of acomp_reqs and buffers. Patch 10) Introduce a separate per-cpu "acomp_batch_ctx" member in "struct zswap_pool" to be able to allocate multiple acomp_reqs/buffers for use in batching, as needed, per core. Patch 11) Allocation of the per-cpu "acomp_batch_ctx" for a zswap_pool. Patch 12) Add a new "sysctl vm.compress-batching" 0/1 switch to enable/disable compress batching dynamically at runtime. Patch 13) zswap_store() IAA compress batching implementation with minimal memory footprint cost per-cpu, and using the new crypto_acomp_batch_compress() iaa_crypto driver API. With the runtime configuration to enable compress batching and the crypto batching API added in v2, this feature will be enabled only on Intel platforms that have IAA. System setup for testing: ========================= Testing of this patch-series was done with mm-unstable as of 10-29-2024, commit 9fb8e0a1c486, without and with this patch-series. Data was gathered on an Intel Sapphire Rapids server, dual-socket 56 cores per socket, 4 IAA devices per socket, 503 GiB RAM and 525G SSD disk partition swap. Core frequency was fixed at 2500MHz. Other kernel configuration parameters: zswap compressor : zstd, deflate-iaa zswap allocator : zsmalloc vm.page-cluster : 0, 2 IAA "compression verification" is disabled and IAA is run in the the async poll mode (the defaults with this series). 2WQs are configured per IAA device. Compress jobs from all cores on a socket are distributed among all 4 IAA devices on the same socket. I ran experiments with these workloads: 1) usemem 30 processes with these large folios enabled to "always": - 16k/32k/64k - 2048k 2) Kernel compilation allmodconfig with 2G max memory, run in tmpfs with these large folios enabled to "always": - 16k/32k/64k Performance testing (usemem30): =============================== The vm-scalability "usemem" test was run in a cgroup whose memory.high was fixed at 150G. The is no swap limit set for the cgroup. 30 usemem processes were run, each allocating and writing 10G of memory, and sleeping for 10 sec before exiting: usemem --init-time -w -O -s 10 -n 30 10g 16k/32/64k folios: usemem30/deflate-iaa: ======================================== ------------------------------------------------------------------------------- mm-unstable-10-29-2024 v2 of this patch-series ------------------------------------------------------------------------------- zswap compressor deflate-iaa deflate-iaa deflate-iaa vm.compress-batching n/a 0 1 vm.page-cluster 2 2 2 ------------------------------------------------------------------------------- Total throughput (KB/s) 7,756,632 7,753,984 8,075,817 Avg throughput (KB/s) 258,554 258,466 269,193 elapsed time (sec) 87.75 88.71 85.82 sys time (sec) 2,073.04 2,147.47 2,030.52 ------------------------------------------------------------------------------- memcg_high 715,854 714,238 720,459 memcg_swap_fail 1,194 1,175 1,250 zswpout 64,510,869 64,510,832 64,511,219 zswpin 458 456 450 pswpout 0 0 0 pswpin 0 0 0 thp_swpout 0 0 0 thp_swpout_fallback 0 0 0 16kB-mthp_swpout_fallback 0 0 0 32kB-mthp_swpout_fallback 0 0 0 64kB-mthp_swpout_fallback 1,194 1,175 1,250 pgmajfault 3,183 3,513 3,116 swap_ra 108 125 116 swap_ra_hit 45 65 43 ZSWPOUT-16kB 2 3 3 ZSWPOUT-32kB 1 1 2 ZSWPOUT-64kB 4,030,658 4,030,672 4,030,624 SWPOUT-16kB 0 0 0 SWPOUT-32kB 0 0 0 SWPOUT-64kB 0 0 0 ------------------------------------------------------------------------------- 16k/32/64k folios: usemem30/zstd: ================================= ------------------------------------------------------------------------------- mm-unstable-10-29-2024 v2 of this patch-series ------------------------------------------------------------------------------- zswap compressor zstd zstd vm.compress-batching n/a 0 vm.page-cluster 2 2 ----------------------------------------------------------------------------- Total throughput (KB/s) 6,054,147 6,109,360 Avg throughput (KB/s) 201,804 203,645 elapsed time (sec) 111.66 111.72 sys time (sec) 2,693.21 2,685.27 ----------------------------------------------------------------------------- memcg_high 489,133 480,524 memcg_swap_fail 1,045 1,308 zswpout 48,931,716 48,931,540 zswpin 407 394 pswpout 0 0 pswpin 0 0 thp_swpout 0 0 thp_swpout_fallback 0 0 16kB-mthp_swpout_fallback 0 0 32kB-mthp_swpout_fallback 0 0 64kB-mthp_swpout_fallback 1,045 1,308 pgmajfault 3,095 3,424 swap_ra 136 101 swap_ra_hit 86 50 ZSWPOUT-16kB 2 4 ZSWPOUT-32kB 0 2 ZSWPOUT-64kB 3,057,161 3,056,927 SWPOUT-16kB 0 0 SWPOUT-32kB 0 0 SWPOUT-64kB 0 0 ----------------------------------------------------------------------------- 2M folios: usemem30/deflate-iaa: ================================ ------------------------------------------------------------------------------- mm-unstable-10-29-2024 v2 of this patch-series ------------------------------------------------------------------------------- zswap compressor deflate-iaa deflate-iaa deflate-iaa vm.compress-batching n/a 0 1 vm.page-cluster 2 2 2 ------------------------------------------------------------------------------- Total throughput (KB/s) 7,948,345 8,096,440 8,165,171 Avg throughput (KB/s) 264,944 269,881 272,172 elapsed time (sec) 88.18 87.13 87.30 sys time (sec) 2,067.56 2,018.08 2,046.79 ------------------------------------------------------------------------------- memcg_high 91,002 87,243 92,084 memcg_swap_fail 39 56 54 zswpout 64,518,833 64,520,439 64,520,116 zswpin 413 452 504 pswpout 0 0 0 pswpin 0 0 0 thp_swpout 0 0 0 thp_swpout_fallback 39 56 54 2048kB-mthp_swpout_fallback 39 56 54 pgmajfault 10,946 15,737 9,645 swap_ra 23,456 36,495 19,247 swap_ra_hit 23,406 36,431 19,193 ZSWPOUT-2048kB 125,915 125,913 125,912 SWPOUT-2048kB 0 0 0 ------------------------------------------------------------------------------- 2M folios: usemem30/zstd: ========================= ------------------------------------------------------------------------------- mm-unstable-10-29-2024 v2 of this patch-series ------------------------------------------------------------------------------- zswap compressor zstd zstd vm.compress-batching n/a 0 vm.page-cluster 2 2 ----------------------------------------------------------------------------- Total throughput (KB/s) 6,300,116 6,278,179 Avg throughput (KB/s) 210,003 209,272 elapsed time (sec) 110.21 111.72 sys time (sec) 2,504.45 2,542.59 ----------------------------------------------------------------------------- memcg_high 57,036 60,090 memcg_swap_fail 61 50 zswpout 48,934,256 48,904,582 zswpin 387 380 pswpout 0 0 pswpin 0 0 thp_swpout 0 0 thp_swpout_fallback 61 50 2048kB-mthp_swpout_fallback 61 50 pgmajfault 3,713 6,146 swap_ra 2,004 8,133 swap_ra_hit 1,960 8,088 ZSWPOUT-2048kB 95,511 95,460 SWPOUT-2048kB 0 0 ----------------------------------------------------------------------------- Performance testing (Kernel compilation, allmodconfig): ======================================================= The experiments with kernel compilation test in tmpfs use the "allmodconfig" that takes ~12 minutes, and has considerable swapout activity. The cgroup's memory.max is set to 2G. 16k/32k/64k folios: Kernel compilation/allmodconfig/deflate-iaa: ================================================================ ------------------------------------------------------------------------------- mm-unstable-10-29-2024 v2 of this patch-series ------------------------------------------------------------------------------- zswap compressor deflate-iaa deflate-iaa deflate-iaa vm.compress-batching n/a 0 1 vm.page-cluster 0 0 0 ------------------------------------------------------------------------------- real_sec 801.25 790.87 768.92 user_sec 15,776.31 15,755.97 15,753.89 sys_sec 4,250.34 3,877.02 3,892.17 Max_Res_Set_Size_KB 1,869,428 1,873,376 1,871,600 ------------------------------------------------------------------------------- memcg_high 0 0 0 memcg_swap_fail 0 0 0 zswpout 106,798,327 105,469,307 104,528,841 zswpin 31,542,093 30,469,671 30,596,840 pswpout 774 290 80 pswpin 370 288 59 thp_swpout 0 0 0 thp_swpout_fallback 0 0 0 16kB-mthp_swpout_fallback 0 0 0 32kB-mthp_swpout_fallback 0 0 0 64kB-mthp_swpout_fallback 16,340 12,633 12,000 pgmajfault 33,983,602 32,783,214 32,731,862 swap_ra 0 0 0 swap_ra_hit 1,467 5,112 3,854 ZSWPOUT-16kB 1,475,121 1,435,571 1,426,738 ZSWPOUT-32kB 821,119 813,202 790,658 ZSWPOUT-64kB 3,483,295 3,490,244 3,435,056 SWPOUT-16kB 1 0 0 SWPOUT-32kB 3 0 0 SWPOUT-64kB 40 18 4 ------------------------------------------------------------------------------- 16k/32k/64k folios: Kernel compilation/allmodconfig/zstd: ========================================================= ------------------------------------------------------------------------------- mm-unstable-10-29-2024 v2 of this patch-series ------------------------------------------------------------------------------- zswap compressor zstd zstd vm.compress-batching n/a 0 vm.page-cluster 0 0 ------------------------------------------------------------------------------- real_sec 812.38 800.09 user_sec 15,774.12 15,771.02 sys_sec 5,283.64 5,257.05 Max_Res_Set_Size_KB 1,872,688 1,873,444 ------------------------------------------------------------------------------- memcg_high 0 0 memcg_swap_fail 0 0 zswpout 91,540,018 90,338,507 zswpin 26,421,271 26,485,837 pswpout 64 144 pswpin 64 114 thp_swpout 0 0 thp_swpout_fallback 0 0 16kB-mthp_swpout_fallback 0 0 32kB-mthp_swpout_fallback 0 0 64kB-mthp_swpout_fallback 4,509 566 pgmajfault 28,341,722 28,427,509 swap_ra 0 0 swap_ra_hit 3,359 2,931 ZSWPOUT-16kB 1,287,206 1,266,947 ZSWPOUT-32kB 707,746 700,270 ZSWPOUT-64kB 2,985,002 2,940,288 SWPOUT-16kB 0 0 SWPOUT-32kB 0 0 SWPOUT-64kB 4 9 ------------------------------------------------------------------------------- Summary: ======== The performance testing data with usemem 30 processes and kernel compilation test show throughput gains and elapsed/sys time reduction with zswap_store() large folios using IAA compress batching. The iaa_crypto wq stats will show almost the same number of compress calls for wq.1 of all IAA devices. wq.0 will handle decompress calls exclusively. We see a latency reduction of 2.5% by distributing compress jobs among all IAA devices on the socket (based on v1 data). We can expect to see even more significant performance and throughput improvements if we use the parallelism offered by IAA to batch compress the pages comprising a batch of 4K (really any-order) folios, not just batching within large folios. This is the reclaim batching patch 13 in v1, which will be submitted in a separate patch-series. Our internal validation of IAA compress/decompress batching in highly contended Sapphire Rapids server setups with workloads running on 72 cores for ~25 minutes under stringent memory limit constraints have shown up to 50% reduction in sys time and 3.5% reduction in workload run time as compared to software compressors. Changes since v2: ================= 1) Rebased to mm-unstable as of 11-5-2024, commit 7994b7ea6ac8. 2) Fixed an issue in zswap_create_acomp_ctx() with checking for NULL returned by kmalloc_node() for acomp_ctx->buffers and for acomp_ctx->reqs. 3) Fixed a bug in zswap_pool_can_batch() for returning true if pool->can_batch_comp is found to be equal to BATCH_COMP_ENABLED, and if the per-cpu acomp_batch_ctx tests true for batching resources having been allocated on this cpu. Also, changed from per_cpu_ptr() to raw_cpu_ptr(). 4) Incorporated the zswap_store_propagate_errors() compilation warning fix suggested by Dan Carpenter. Thanks Dan! 5) Replaced the references to SWAP_CRYPTO_SUB_BATCH_SIZE in comments in zswap.h, with SWAP_CRYPTO_BATCH_SIZE. Changes since v1: ================= 1) Rebased to mm-unstable as of 11-1-2024, commit 5c4cf96cd702. 2) Incorporated Herbert's suggestions to use an acomp_req flag to indicate async/poll mode, and to encapsulate the polling functionality in the iaa_crypto driver. Thanks Herbert! 3) Incorporated Herbert's and Yosry's suggestions to implement the batching API in iaa_crypto and to make its use seamless from zswap's perspective. Thanks Herbert and Yosry! 4) Incorporated Yosry's suggestion to make it more convenient for the user to enable compress batching, while minimizing the memory footprint cost. Thanks Yosry! 5) Incorporated Yosry's suggestion to de-couple the shrink_folio_list() reclaim batching patch from this series, since it requires a broader discussion. Requesting the maintainers & reviewers to kindly review v3 of this patch-series instead of v2. I would greatly appreciate code review comments for the iaa_crypto driver and mm patches included in this series! Thanks, Kanchana Kanchana P Sridhar (13): crypto: acomp - Define two new interfaces for compress/decompress batching. crypto: iaa - Add an acomp_req flag CRYPTO_ACOMP_REQ_POLL to enable async mode. crypto: iaa - Implement compress/decompress batching API in iaa_crypto. crypto: iaa - Make async mode the default. crypto: iaa - Disable iaa_verify_compress by default. crypto: iaa - Change cpu-to-iaa mappings to evenly balance cores to IAAs. crypto: iaa - Distribute compress jobs to all IAA devices on a NUMA node. mm: zswap: acomp_ctx mutex lock/unlock optimizations. mm: zswap: Modify struct crypto_acomp_ctx to be configurable in nr of acomp_reqs. mm: zswap: Add a per-cpu "acomp_batch_ctx" to struct zswap_pool. mm: zswap: Allocate acomp_batch_ctx resources for a given zswap_pool. mm: Add sysctl vm.compress-batching switch for compress batching during swapout. mm: zswap: Compress batching with Intel IAA in zswap_store() of large folios. crypto/acompress.c | 2 + drivers/crypto/intel/iaa/iaa_crypto_main.c | 717 +++++++++++++++-- include/crypto/acompress.h | 87 +++ include/crypto/internal/acompress.h | 16 + include/linux/mm.h | 2 + include/linux/zswap.h | 91 +++ kernel/sysctl.c | 9 + mm/swap.c | 6 + mm/zswap.c | 865 +++++++++++++++++++-- 9 files changed, 1701 insertions(+), 94 deletions(-) base-commit: 7994b7ea6ac880efd0c38fedfbffd5ab8b1b7b2b