From patchwork Wed Jun 7 16:12:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: ~hyman X-Patchwork-Id: 1792016 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4QcB220027z20QH for ; Thu, 8 Jun 2023 14:24:41 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q77BH-00067S-Ov; Thu, 08 Jun 2023 00:23:27 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q74z5-0006RZ-LE for qemu-devel@nongnu.org; Wed, 07 Jun 2023 22:02:43 -0400 Received: from mail-b.sr.ht ([173.195.146.151]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q74z3-0000De-Pe for qemu-devel@nongnu.org; Wed, 07 Jun 2023 22:02:43 -0400 Authentication-Results: mail-b.sr.ht; dkim=none Received: from git.sr.ht (unknown [173.195.146.142]) by mail-b.sr.ht (Postfix) with ESMTPSA id CE22B11F133; Thu, 8 Jun 2023 02:02:39 +0000 (UTC) From: ~hyman Date: Thu, 08 Jun 2023 00:12:40 +0800 Subject: [PATCH QEMU v5 6/8] migration: Implement dirty-limit convergence algo MIME-Version: 1.0 Message-ID: <168618975839.6361.17407633874747688653-6@git.sr.ht> X-Mailer: git.sr.ht In-Reply-To: <168618975839.6361.17407633874747688653-0@git.sr.ht> To: qemu-devel Cc: Peter Xu , Paolo Bonzini , Juan Quintela , "Dr. David Alan Gilbert" , Eric Blake , Markus Armbruster , Thomas Huth , Laurent Vivier , Richard Henderson , Philippe =?utf-8?q?Mathie?= =?utf-8?q?u-Daud=C3=A9?= , Hyman =?utf-8?b?SHVhbmco6buE?= =?utf-8?b?5YuHKQ==?= Received-SPF: pass client-ip=173.195.146.151; envelope-from=outgoing@sr.ht; helo=mail-b.sr.ht X-Spam_score_int: -3 X-Spam_score: -0.4 X-Spam_bar: / X-Spam_report: (-0.4 / 5.0 requ) BAYES_00=-1.9, DATE_IN_PAST_06_12=1.543, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-Mailman-Approved-At: Thu, 08 Jun 2023 00:23:23 -0400 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: ~hyman Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Hyman Huang(黄勇) Implement dirty-limit convergence algo for live migration, which is kind of like auto-converge algo but using dirty-limit instead of cpu throttle to make migration convergent. Enable dirty page limit if dirty_rate_high_cnt greater than 2 when dirty-limit capability enabled, Disable dirty-limit if migration be cancled. Note that "set_vcpu_dirty_limit", "cancel_vcpu_dirty_limit" commands are not allowed during dirty-limit live migration. Signed-off-by: Hyman Huang(黄勇) Signed-off-by: Markus Armbruster --- migration/migration.c | 3 ++ migration/ram.c | 63 ++++++++++++++++++++++++++++++++---------- migration/trace-events | 1 + softmmu/dirtylimit.c | 22 +++++++++++++++ 4 files changed, 74 insertions(+), 15 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index dc05c6f6ea..4278b48af0 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -165,6 +165,9 @@ void migration_cancel(const Error *error) if (error) { migrate_set_error(current_migration, error); } + if (migrate_dirty_limit()) { + qmp_cancel_vcpu_dirty_limit(false, -1, NULL); + } migrate_fd_cancel(current_migration); } diff --git a/migration/ram.c b/migration/ram.c index 132f1a81d9..d26c7a8193 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -46,6 +46,7 @@ #include "qapi/error.h" #include "qapi/qapi-types-migration.h" #include "qapi/qapi-events-migration.h" +#include "qapi/qapi-commands-migration.h" #include "qapi/qmp/qerror.h" #include "trace.h" #include "exec/ram_addr.h" @@ -59,6 +60,8 @@ #include "multifd.h" #include "sysemu/runstate.h" #include "options.h" +#include "sysemu/dirtylimit.h" +#include "sysemu/kvm.h" #include "hw/boards.h" /* for machine_dump_guest_core() */ @@ -983,6 +986,30 @@ static void migration_update_rates(RAMState *rs, int64_t end_time) } } +/* + * Enable dirty-limit to throttle down the guest + */ +static void migration_dirty_limit_guest(void) +{ + static int64_t quota_dirtyrate; + MigrationState *s = migrate_get_current(); + + /* + * If dirty limit already enabled and migration parameter + * vcpu-dirty-limit untouched. + */ + if (dirtylimit_in_service() && + quota_dirtyrate == s->parameters.vcpu_dirty_limit) { + return; + } + + quota_dirtyrate = s->parameters.vcpu_dirty_limit; + + /* Set or update quota dirty limit */ + qmp_set_vcpu_dirty_limit(false, -1, quota_dirtyrate, NULL); + trace_migration_dirty_limit_guest(quota_dirtyrate); +} + static void migration_trigger_throttle(RAMState *rs) { uint64_t threshold = migrate_throttle_trigger_threshold(); @@ -991,26 +1018,32 @@ static void migration_trigger_throttle(RAMState *rs) uint64_t bytes_dirty_period = rs->num_dirty_pages_period * TARGET_PAGE_SIZE; uint64_t bytes_dirty_threshold = bytes_xfer_period * threshold / 100; - /* During block migration the auto-converge logic incorrectly detects - * that ram migration makes no progress. Avoid this by disabling the - * throttling logic during the bulk phase of block migration. */ - if (blk_mig_bulk_active()) { - return; - } + /* + * The following detection logic can be refined later. For now: + * Check to see if the ratio between dirtied bytes and the approx. + * amount of bytes that just got transferred since the last time + * we were in this routine reaches the threshold. If that happens + * twice, start or increase throttling. + */ - if (migrate_auto_converge()) { - /* The following detection logic can be refined later. For now: - Check to see if the ratio between dirtied bytes and the approx. - amount of bytes that just got transferred since the last time - we were in this routine reaches the threshold. If that happens - twice, start or increase throttling. */ + if ((bytes_dirty_period > bytes_dirty_threshold) && + (++rs->dirty_rate_high_cnt >= 2)) { + rs->dirty_rate_high_cnt = 0; + /* + * During block migration the auto-converge logic incorrectly detects + * that ram migration makes no progress. Avoid this by disabling the + * throttling logic during the bulk phase of block migration + */ + if (blk_mig_bulk_active()) { + return; + } - if ((bytes_dirty_period > bytes_dirty_threshold) && - (++rs->dirty_rate_high_cnt >= 2)) { + if (migrate_auto_converge()) { trace_migration_throttle(); - rs->dirty_rate_high_cnt = 0; mig_throttle_guest_down(bytes_dirty_period, bytes_dirty_threshold); + } else if (migrate_dirty_limit()) { + migration_dirty_limit_guest(); } } } diff --git a/migration/trace-events b/migration/trace-events index cdaef7a1ea..c5cb280d95 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -91,6 +91,7 @@ migration_bitmap_sync_start(void) "" migration_bitmap_sync_end(uint64_t dirty_pages) "dirty_pages %" PRIu64 migration_bitmap_clear_dirty(char *str, uint64_t start, uint64_t size, unsigned long page) "rb %s start 0x%"PRIx64" size 0x%"PRIx64" page 0x%lx" migration_throttle(void) "" +migration_dirty_limit_guest(int64_t dirtyrate) "guest dirty page rate limit %" PRIi64 " MB/s" ram_discard_range(const char *rbname, uint64_t start, size_t len) "%s: start: %" PRIx64 " %zx" ram_load_loop(const char *rbname, uint64_t addr, int flags, void *host) "%s: addr: 0x%" PRIx64 " flags: 0x%x host: %p" ram_load_postcopy_loop(int channel, uint64_t addr, int flags) "chan=%d addr=0x%" PRIx64 " flags=0x%x" diff --git a/softmmu/dirtylimit.c b/softmmu/dirtylimit.c index 3f1103b04b..ee47158986 100644 --- a/softmmu/dirtylimit.c +++ b/softmmu/dirtylimit.c @@ -440,6 +440,8 @@ void qmp_cancel_vcpu_dirty_limit(bool has_cpu_index, int64_t cpu_index, Error **errp) { + MigrationState *ms = migrate_get_current(); + if (!kvm_enabled() || !kvm_dirty_ring_enabled()) { return; } @@ -453,6 +455,15 @@ void qmp_cancel_vcpu_dirty_limit(bool has_cpu_index, return; } + if (migration_is_running(ms->state) && + (!qemu_thread_is_self(&ms->thread)) && + migrate_dirty_limit() && + dirtylimit_in_service()) { + error_setg(errp, "can't cancel dirty page limit while" + " migration is running"); + return; + } + dirtylimit_state_lock(); if (has_cpu_index) { @@ -488,6 +499,8 @@ void qmp_set_vcpu_dirty_limit(bool has_cpu_index, uint64_t dirty_rate, Error **errp) { + MigrationState *ms = migrate_get_current(); + if (!kvm_enabled() || !kvm_dirty_ring_enabled()) { error_setg(errp, "dirty page limit feature requires KVM with" " accelerator property 'dirty-ring-size' set'"); @@ -504,6 +517,15 @@ void qmp_set_vcpu_dirty_limit(bool has_cpu_index, return; } + if (migration_is_running(ms->state) && + (!qemu_thread_is_self(&ms->thread)) && + migrate_dirty_limit() && + dirtylimit_in_service()) { + error_setg(errp, "can't cancel dirty page limit while" + " migration is running"); + return; + } + dirtylimit_state_lock(); if (!dirtylimit_in_service()) {