From 510991b65a9d55f1408e6b660a8e505a86467b2d Mon Sep 17 00:00:00 2001 From: Erik Skultety Date: Wed, 17 Feb 2016 09:55:19 +0100 Subject: [PATCH] virt-admin: Introduce srv-threadpool-info and srv-threadpool-set commands Wire up the server threadpool tunable APIs to virt-admin client. Also, provide a man page for both commands. Signed-off-by: Erik Skultety --- tools/virt-admin.c | 185 +++++++++++++++++++++++++++++++++++++++++++ tools/virt-admin.pod | 77 ++++++++++++++++++ 2 files changed, 262 insertions(+) diff --git a/tools/virt-admin.c b/tools/virt-admin.c index 195088bdd8..22160ad929 100644 --- a/tools/virt-admin.c +++ b/tools/virt-admin.c @@ -352,6 +352,174 @@ cmdSrvList(vshControl *ctl, const vshCmd *cmd ATTRIBUTE_UNUSED) return ret; } + +/* --------------------------- + * Command srv-threadpool-info + * --------------------------- + */ + +static const vshCmdInfo info_srv_threadpool_info[] = { + {.name = "help", + .data = N_("get server workerpool parameters") + }, + {.name = "desc", + .data = N_("Retrieve threadpool attributes from a server. ") + }, + {.name = NULL} +}; + +static const vshCmdOptDef opts_srv_threadpool_info[] = { + {.name = "server", + .type = VSH_OT_DATA, + .flags = VSH_OFLAG_REQ, + .help = N_("Server to retrieve threadpool attributes from."), + }, + {.name = NULL} +}; + +static bool +cmdSrvThreadpoolInfo(vshControl *ctl, const vshCmd *cmd) +{ + bool ret = false; + virTypedParameterPtr params = NULL; + int nparams = 0; + size_t i; + const char *srvname = NULL; + virAdmServerPtr srv = NULL; + vshAdmControlPtr priv = ctl->privData; + + if (vshCommandOptStringReq(ctl, cmd, "server", &srvname) < 0) + return false; + + if (!(srv = virAdmConnectLookupServer(priv->conn, srvname, 0))) + goto cleanup; + + if (virAdmServerGetThreadPoolParameters(srv, ¶ms, + &nparams, 0) < 0) { + vshError(ctl, "%s", + _("Unable to get server workerpool parameters")); + goto cleanup; + } + + for (i = 0; i < nparams; i++) + vshPrint(ctl, "%-15s: %d\n", params[i].field, params[i].value.ui); + + ret = true; + + cleanup: + virTypedParamsFree(params, nparams); + if (srv) + virAdmServerFree(srv); + return ret; +} + +/* -------------------------- + * Command srv-threadpool-set + * -------------------------- + */ + +static const vshCmdInfo info_srv_threadpool_set[] = { + {.name = "help", + .data = N_("set server workerpool parameters") + }, + {.name = "desc", + .data = N_("Tune threadpool attributes on a server. See OPTIONS for " + "currently supported attributes.") + }, + {.name = NULL} +}; + +static const vshCmdOptDef opts_srv_threadpool_set[] = { + {.name = "server", + .type = VSH_OT_DATA, + .flags = VSH_OFLAG_REQ, + .help = N_("Server to alter threadpool attributes on."), + }, + {.name = "min-workers", + .type = VSH_OT_INT, + .help = N_("Change bottom limit to number of workers."), + }, + {.name = "max-workers", + .type = VSH_OT_INT, + .help = N_("Change upper limit to number of workers."), + }, + {.name = "priority-workers", + .type = VSH_OT_INT, + .help = N_("Change the current number of priority workers"), + }, + {.name = NULL} +}; + +static bool +cmdSrvThreadpoolSet(vshControl *ctl, const vshCmd *cmd) +{ + bool ret = false; + int rv = 0; + unsigned int val, min, max; + int maxparams = 0; + int nparams = 0; + const char *srvname = NULL; + virTypedParameterPtr params = NULL; + virAdmServerPtr srv = NULL; + vshAdmControlPtr priv = ctl->privData; + + if (vshCommandOptStringReq(ctl, cmd, "server", &srvname) < 0) + return false; + +#define PARSE_CMD_TYPED_PARAM(NAME, FIELD) \ + if ((rv = vshCommandOptUInt(ctl, cmd, NAME, &val)) < 0) { \ + vshError(ctl, _("Unable to parse integer parameter '%s'"), NAME); \ + goto cleanup; \ + } else if (rv > 0) { \ + if (virTypedParamsAddUInt(¶ms, &nparams, &maxparams, \ + FIELD, val) < 0) \ + goto save_error; \ + } + + PARSE_CMD_TYPED_PARAM("max-workers", VIR_THREADPOOL_WORKERS_MAX); + PARSE_CMD_TYPED_PARAM("min-workers", VIR_THREADPOOL_WORKERS_MIN); + PARSE_CMD_TYPED_PARAM("priority-workers", VIR_THREADPOOL_WORKERS_PRIORITY); + +#undef PARSE_CMD_TYPED_PARAM + + if (!nparams) { + vshError(ctl, "%s", + _("At least one of options --min-workers, --max-workers, " + "--priority-workers is mandatory ")); + goto cleanup; + } + + if (virTypedParamsGetUInt(params, nparams, + VIR_THREADPOOL_WORKERS_MAX, &max) && + virTypedParamsGetUInt(params, nparams, + VIR_THREADPOOL_WORKERS_MIN, &min) && min > max) { + vshError(ctl, "%s", _("--min-workers must be less than --max-workers")); + goto cleanup; + } + + if (!(srv = virAdmConnectLookupServer(priv->conn, srvname, 0))) + goto cleanup; + + if (virAdmServerSetThreadPoolParameters(srv, params, + nparams, 0) < 0) + goto error; + + ret = true; + + cleanup: + virTypedParamsFree(params, nparams); + if (srv) + virAdmServerFree(srv); + return ret; + + save_error: + vshSaveLibvirtError(); + + error: + vshError(ctl, "%s", _("Unable to change server workerpool parameters")); + goto cleanup; +} + static void * vshAdmConnectionHandler(vshControl *ctl) { @@ -651,12 +819,29 @@ static const vshCmdDef monitoringCmds[] = { .info = info_srv_list, .flags = 0 }, + {.name = "srv-threadpool-info", + .handler = cmdSrvThreadpoolInfo, + .opts = opts_srv_threadpool_info, + .info = info_srv_threadpool_info, + .flags = 0 + }, + {.name = NULL} +}; + +static const vshCmdDef managementCmds[] = { + {.name = "srv-threadpool-set", + .handler = cmdSrvThreadpoolSet, + .opts = opts_srv_threadpool_set, + .info = info_srv_threadpool_set, + .flags = 0 + }, {.name = NULL} }; static const vshCmdGrp cmdGroups[] = { {"Virt-admin itself", "virt-admin", vshAdmCmds}, {"Monitoring commands", "monitor", monitoringCmds}, + {"Management commands", "management", managementCmds}, {NULL, NULL, NULL} }; diff --git a/tools/virt-admin.pod b/tools/virt-admin.pod index f2b1012651..411951a2d7 100644 --- a/tools/virt-admin.pod +++ b/tools/virt-admin.pod @@ -145,6 +145,83 @@ I were set, libvirtd:///system is used. =back +=head1 SERVER COMMANDS + +Following commands manipulate daemon's server internal configuration. +The I is specified by its name. + +=over 4 + +=item B I + +Retrieve server's threadpool attributes. These attributes include: + +=over 4 + +=item I +as the bottom limit to the number of active workers, + +=item I +as the top limit to the number of active workers, + +=item I +as the current number of workers in the threadpool, + +=item I +as the current number of workers available for a task, + +=item I +as the current number of priority workers in the threadpool, and + +=item I +as the current depth of threadpool's job queue. + +=back + +B + +Each daemon server utilizes a threadpool to accomplish tasks requested by +clients connected to it. Every time a client request arrives to the server, +it checks whether there is a worker available to accomplish the given task or +it should create a new worker for the job (rather than being destroyed, the +worker becomes free once the task is finished). Creating new workers, however, +is only possible when the current number of workers is still below the +configured upper limit. + +In addition to these 'standard' workers, a threadpool also contains a special +set of workers called I workers. Their purpose is to perform tasks +that, unlike tasks carried out by normal workers, are within libvirt's full +control and libvirt guarantees that such a task cannot hang, thus will always +finish. An example of such a task this would be destroying a domain: + $ virsh destroy . + +=item B I [I<--min-workers> B] +[I<--max-workers> B] [I<--priority-workers> B] + +Change threadpool attributes on a server. Only a fraction of all attributes as +described in I is supported for the setter. + +=over 4 + +=item I<--min-workers> + +The bottom limit to number of active workers in a threadpool. + +=item I<--max-workers> + +The upper limit to number of active workers in a threadpool. If used in +combination with option I<--min-workers>, the value for the upper limit has to +be greater than the value for the bottom limit, otherwise the command results +in an error. + +=item I<--priority-workers> + +The current number of active priority workers in a threadpool. + +=back + +=back + =head1 ENVIRONMENT The following environment variables can be set to alter the behaviour