[libvirt RFCv11 24/33] tools: add parallel parameter to virsh save command

Signed-off-by: Claudio Fontana <cfontana(a)suse.de&gt; --- docs/manpages/virsh.rst | 11 ++++++++++- tools/virsh-domain.c | 24 ++++++++++++++++++++++-- 2 files changed, 32 insertions(+), 3 deletions(-) diff --git a/docs/manpages/virsh.rst b/docs/manpages/virsh.rst index 965b89c99d..9f33b0aaef 100644 --- a/docs/manpages/virsh.rst +++ b/docs/manpages/virsh.rst @@ -3803,6 +3803,7 @@ save :: save domain state-file [--bypass-cache] [--xml file] + [--parallel] [--parallel-connections connections] [{--running | --paused}] [--verbose] Saves a running domain (RAM, but not disk state) to a state file so that @@ -3810,8 +3811,10 @@ it can be restored later. Once saved, the domain will no longer be running on the system, thus the memory allocated for the domain will be free for other domains to use. ``virsh restore`` restores from this state file. + If *--bypass-cache* is specified, the save will avoid the file system -cache, although this may slow down the operation. +cache; depending on the specific scenario this may slow down or speed up +the operation. The progress may be monitored using ``domjobinfo`` virsh command and canceled with ``domjobabort`` command (sent by another virsh instance). Another option @@ -3833,6 +3836,12 @@ based on the state the domain was in when the save was done; passing either the *--running* or *--paused* flag will allow overriding which state the ``restore`` should use. +*--parallel* option will cause the save data to be sent over multiple +parallel connections to the file. The number of extra connections +can be set using *--parallel-connections*. + +Parallel connections help in speeding up large save operations. + Domain saved state files assume that disk images will be unchanged between the creation and restore point. For a more complete system restore point, where the disk state is saved alongside the memory diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c index a3f007a1d2..7a313cb29e 100644 --- a/tools/virsh-domain.c +++ b/tools/virsh-domain.c @@ -4174,6 +4174,14 @@ static const vshCmdOptDef opts_save[] = { .type = VSH_OT_BOOL, .help = N_("avoid file system cache when saving") }, + {.name = "parallel", + .type = VSH_OT_BOOL, + .help = N_("enable parallel save") + }, + {.name = "parallel-connections", + .type = VSH_OT_INT, + .help = N_("number of extra connections to use for parallel save") + }, {.name = "xml", .type = VSH_OT_STRING, .completer = virshCompletePathLocalExisting, @@ -4206,6 +4214,8 @@ doSave(void *opaque) virTypedParameterPtr params = NULL; int nparams = 0; int maxparams = 0; + int intOpt = 0; + int rv = -1; unsigned int flags = 0; const char *xmlfile = NULL; g_autofree char *xml = NULL; @@ -4227,6 +4237,15 @@ doSave(void *opaque) } if (vshCommandOptBool(cmd, "bypass-cache")) flags |= VIR_DOMAIN_SAVE_BYPASS_CACHE; + if (vshCommandOptBool(cmd, "parallel")) + flags |= VIR_DOMAIN_SAVE_PARALLEL; + if ((rv = vshCommandOptInt(ctl, cmd, "parallel-connections", &intOpt)) < 0) { + goto out; + } else if (rv > 0) { + if (virTypedParamsAddInt(&params, &nparams, &maxparams, + VIR_DOMAIN_SAVE_PARAM_PARALLEL_CONNECTIONS, intOpt) < 0) + goto out; + } if (vshCommandOptBool(cmd, "running")) flags |= VIR_DOMAIN_SAVE_RUNNING; if (vshCommandOptBool(cmd, "paused")) @@ -4247,8 +4266,9 @@ doSave(void *opaque) goto out; } } - - if (flags || xml) { + if (flags & VIR_DOMAIN_SAVE_PARALLEL) { + rc = virDomainSaveParams(dom, params, nparams, flags); + } else if (flags || xml) { rc = virDomainSaveFlags(dom, to, xml, flags); } else { rc = virDomainSave(dom, to); -- 2.26.2