[PATCH v2 09/22] qemu: add config parameter to control auto-save bypass cache

When doing managed save of VMs, triggered by OS shutdown, it may be desirable to control cache usage. Reviewed-by: Peter Krempa <pkrempa(a)redhat.com&gt; Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com&gt; --- src/qemu/libvirtd_qemu.aug | 1 + src/qemu/qemu.conf.in | 8 ++++++++ src/qemu/qemu_conf.c | 3 +++ src/qemu/qemu_conf.h | 1 + src/qemu/qemu_driver.c | 1 + src/qemu/test_libvirtd_qemu.aug.in | 1 + 6 files changed, 15 insertions(+) diff --git a/src/qemu/libvirtd_qemu.aug b/src/qemu/libvirtd_qemu.aug index 8cb1b144b9..9fa6398d8d 100644 --- a/src/qemu/libvirtd_qemu.aug +++ b/src/qemu/libvirtd_qemu.aug @@ -102,6 +102,7 @@ module Libvirtd_qemu = | str_entry "auto_shutdown_try_shutdown" | str_entry "auto_shutdown_poweroff" | int_entry "auto_shutdown_wait" + | bool_entry "auto_save_bypass_cache" let process_entry = str_entry "hugetlbfs_mount" | str_entry "bridge_helper" diff --git a/src/qemu/qemu.conf.in b/src/qemu/qemu.conf.in index 5a9bfd90e8..5643e849ad 100644 --- a/src/qemu/qemu.conf.in +++ b/src/qemu/qemu.conf.in @@ -689,6 +689,14 @@ # is currently 30 secs) #auto_shutdown_wait = 30 +# When a domain is configured to be auto-saved on shutdown, enabling +# this flag has the same effect as using the VIR_DOMAIN_SAVE_BYPASS_CACHE +# flag with the virDomainManagedSave API. That is, the system will +# avoid using the file system cache when writing any managed state +# file, but may cause slower operation. +# +#auto_save_bypass_cache = 0 + # If provided by the host and a hugetlbfs mount point is configured, # a guest may request huge page backing. When this mount point is # unspecified here, determination of a host mount point in /proc/mounts diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c index d1ae5fa308..6161a3c8d6 100644 --- a/src/qemu/qemu_conf.c +++ b/src/qemu/qemu_conf.c @@ -732,6 +732,9 @@ virQEMUDriverConfigLoadSaveEntry(virQEMUDriverConfig *cfg, if (virConfGetValueUInt(conf, "auto_shutdown_wait", &cfg->autoShutdownWait) < 0) return -1; + if (virConfGetValueBool(conf, "auto_save_bypass_cache", + &cfg->autoSaveBypassCache) < 0) + return -1; return 0; } diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h index f6fcfe444d..06c917ba3e 100644 --- a/src/qemu/qemu_conf.h +++ b/src/qemu/qemu_conf.h @@ -206,6 +206,7 @@ struct _virQEMUDriverConfig { virDomainDriverAutoShutdownScope autoShutdownTryShutdown; virDomainDriverAutoShutdownScope autoShutdownPoweroff; unsigned int autoShutdownWait; + bool autoSaveBypassCache; char *lockManagerName; diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 08e2248852..3932640b79 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -951,6 +951,7 @@ qemuStateStop(void) .tryShutdown = cfg->autoShutdownTryShutdown, .poweroff = cfg->autoShutdownPoweroff, .waitShutdownSecs = cfg->autoShutdownWait, + .saveBypassCache = cfg->autoSaveBypassCache, }; virDomainDriverAutoShutdown(&ascfg); diff --git a/src/qemu/test_libvirtd_qemu.aug.in b/src/qemu/test_libvirtd_qemu.aug.in index 4c6de31199..65d0c20fe1 100644 --- a/src/qemu/test_libvirtd_qemu.aug.in +++ b/src/qemu/test_libvirtd_qemu.aug.in @@ -80,6 +80,7 @@ module Test_libvirtd_qemu = { "auto_shutdown_try_shutdown" = "all" } { "auto_shutdown_poweroff" = "all" } { "auto_shutdown_wait" = "30" } +{ "auto_save_bypass_cache" = "0" } { "hugetlbfs_mount" = "/dev/hugepages" } { "bridge_helper" = "qemu-bridge-helper" } { "set_process_name" = "1" } -- 2.48.1