Upstream kernel introduced new sysfs knob "merge_across_nodes" to specify if pages from different numa nodes can be merged. When set to 0, only pages which physically reside in the memory area of same NUMA node can be merged. When set to 1, pages from all nodes can be merged. This patch supports the tuning by adding new param field "shm-merge-across-nodes".

--- Perhaps two bool options like "--disable-shm-merge-across-nodes", and "--enable-shm-merge-across-nodes" are good, but could the kernel sysfs knob have other values beyond 0 and 1 in future?

+++ b/include/libvirt/libvirt.h.in @@ -4489,6 +4489,16 @@ typedef virMemoryParameter *virMemoryParameterPtr; */ # define VIR_NODE_MEMORY_SHARED_FULL_SCANS "shm_full_scans" +/* VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES: + * + * Macro for typed parameter that represents whether pages from + * different NUMA nodes can be merged, when its value is 0, only + * pages which physically reside in the memory area of same NUMA + * node are merged, otherwise pages from all nodes can be merged.

+ */ +# define VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES "shm_merge_across_nodes"

+ + int virNodeGetMemoryParameters(virConnectPtr conn, virTypedParameterPtr params, int *nparams, diff --git a/src/nodeinfo.c b/src/nodeinfo.c index 021eb05..6002789 100644 --- a/src/nodeinfo.c +++ b/src/nodeinfo.c @@ -1004,6 +1004,13 @@ nodeSetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, /* Out of memory */ if (ret == -2) return -1; + } else if (STREQ(param->field, + VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES)) {

Upstream kernel introduced new sysfs knob "merge_across_nodes" to specify if pages from different numa nodes can be merged. When set to 0, only pages which physically reside in the memory area of same NUMA node can be merged. When set to 1, pages from all nodes can be merged. This patch supports the tuning by adding new param field "shm_merge_across_nodes". --- include/libvirt/libvirt.h.in | 12 ++++++++++++ src/nodeinfo.c | 28 +++++++++++++++++++++++++--- tools/virsh-host.c | 20 ++++++++++++++++++++ tools/virsh.pod | 5 ++++- 4 files changed, 61 insertions(+), 4 deletions(-) diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in index a4e8ca9..1490558 100644 --- a/include/libvirt/libvirt.h.in +++ b/include/libvirt/libvirt.h.in @@ -4490,6 +4490,18 @@ typedef virMemoryParameter *virMemoryParameterPtr; */ # define VIR_NODE_MEMORY_SHARED_FULL_SCANS "shm_full_scans" +/* VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES: + * + * Macro for typed parameter that represents whether pages from + * different NUMA nodes can be merged. The parameter has type int, + * when its value is 0, only pages which physically reside in the + * memory area of same NUMA node are merged; When its value is 1, + * pages from all nodes can be merged. Other values are reserved + * for future use. + */ +# define VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES "shm_merge_across_nodes" + + int virNodeGetMemoryParameters(virConnectPtr conn, virTypedParameterPtr params, int *nparams, diff --git a/src/nodeinfo.c b/src/nodeinfo.c index c0e60d8..8f96b8b 100644 --- a/src/nodeinfo.c +++ b/src/nodeinfo.c @@ -1005,6 +1005,8 @@ nodeSetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, VIR_TYPED_PARAM_UINT, VIR_NODE_MEMORY_SHARED_SLEEP_MILLISECS, VIR_TYPED_PARAM_UINT, + VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES, + VIR_TYPED_PARAM_UINT, NULL)< 0) return -1; @@ -1025,6 +1027,13 @@ nodeSetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, /* Out of memory */ if (ret == -2) return -1; + } else if (STREQ(param->field, + VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES)) { + ret = nodeSetMemoryParameterValue("merge_across_nodes", param); + + /* Out of memory */ + if (ret == -2) + return -1; } } @@ -1060,8 +1069,9 @@ nodeGetMemoryParameterValue(const char *field, if ((tmp = strchr(buf, '\n'))) *tmp = '\0'; - if (STREQ(field, "pages_to_scan") || - STREQ(field, "sleep_millisecs")) + if (STREQ(field, "pages_to_scan") || + STREQ(field, "sleep_millisecs") || + STREQ(field, "merge_across_nodes")) rc = virStrToLong_ui(buf, NULL, 10, (unsigned int *)value); else if (STREQ(field, "pages_shared") || STREQ(field, "pages_sharing") || @@ -1084,7 +1094,7 @@ cleanup: } #endif -#define NODE_MEMORY_PARAMETERS_NUM 7 +#define NODE_MEMORY_PARAMETERS_NUM 8 int nodeGetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, virTypedParameterPtr params ATTRIBUTE_UNUSED, @@ -1096,6 +1106,7 @@ nodeGetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, #ifdef __linux__ unsigned int pages_to_scan; unsigned int sleep_millisecs; + unsigned int merge_across_nodes; unsigned long long pages_shared; unsigned long long pages_sharing; unsigned long long pages_unshared; @@ -1189,6 +1200,17 @@ nodeGetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, break; + case 7: + if (nodeGetMemoryParameterValue("merge_across_nodes", +&merge_across_nodes)< 0) + return -1; + + if (virTypedParameterAssign(param, VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES, + VIR_TYPED_PARAM_UINT, merge_across_nodes)< 0) + return -1; + + break; + default: break; } diff --git a/tools/virsh-host.c b/tools/virsh-host.c index 5cf192d..106f5e9 100644 --- a/tools/virsh-host.c +++ b/tools/virsh-host.c @@ -920,6 +920,8 @@ static const vshCmdOptDef opts_node_memory_tune[] = { {"shm-sleep-millisecs", VSH_OT_INT, VSH_OFLAG_NONE, N_("number of millisecs the shared memory service should " "sleep before next scan")}, + {"shm-merge-across-nodes", VSH_OT_INT, VSH_OFLAG_NONE, + N_("Specifies if pages from different numa nodes can be merged")}, {NULL, 0, 0, NULL} }; @@ -931,6 +933,7 @@ cmdNodeMemoryTune(vshControl *ctl, const vshCmd *cmd) unsigned int flags = 0; unsigned int shm_pages_to_scan = 0; unsigned int shm_sleep_millisecs = 0; + unsigned int shm_merge_across_nodes = 0; bool ret = false; int i = 0; @@ -946,12 +949,21 @@ cmdNodeMemoryTune(vshControl *ctl, const vshCmd *cmd) return false; } + if (vshCommandOptUInt(cmd, "shm-merge-across-nodes", +&shm_merge_across_nodes)< 0) { + vshError(ctl, "%s", _("invalid shm-merge-across-nodes number")); + return false; + } + if (shm_pages_to_scan) nparams++; if (shm_sleep_millisecs) nparams++; + if (shm_merge_across_nodes) + nparams++; + if (nparams == 0) { /* Get the number of memory parameters */ if (virNodeGetMemoryParameters(ctl->conn, NULL,&nparams, flags) != 0) { @@ -1003,6 +1015,14 @@ cmdNodeMemoryTune(vshControl *ctl, const vshCmd *cmd) goto error; } + if (i< nparams&& shm_merge_across_nodes) { + if (virTypedParameterAssign(&params[i++], + VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES, + VIR_TYPED_PARAM_UINT, + shm_merge_across_nodes)< 0) + goto error; + } + if (virNodeSetMemoryParameters(ctl->conn, params, nparams, flags) != 0) goto error; else diff --git a/tools/virsh.pod b/tools/virsh.pod index 2d90b7b..0481e1f 100644 --- a/tools/virsh.pod +++ b/tools/virsh.pod @@ -303,7 +303,10 @@ Allows you to display or set the node memory parameters. I<shm-pages-to-scan> can be used to set the number of pages to scan before the shared memory service goes to sleep; I<shm-sleep-millisecs> can be used to set the number of millisecs the shared memory service should -sleep before next scan. +sleep before next scan; I<shm-merge-across-nodes> specifies if pages from +different numa nodes can be merged. When set to 0, only pages which physically +reside in the memory area of same NUMA node can be merged. When set to 1, +pages from all nodes can be merged. Default to 1. =item B<capabilities>

On Fri, Oct 12, 2012 at 04:25:42PM +0800, Osier Yang wrote: > Upstream kernel introduced new sysfs knob "merge_across_nodes" to > specify if pages from different numa nodes can be merged. When set > to 0, only pages which physically reside in the memory area of > same NUMA node can be merged. When set to 1, pages from all nodes > can be merged. > > This patch supports the tuning by adding new param field > "shm_merge_across_nodes". > --- > include/libvirt/libvirt.h.in | 12 ++++++++++++ > src/nodeinfo.c | 28 +++++++++++++++++++++++++--- > tools/virsh-host.c | 20 ++++++++++++++++++++ > tools/virsh.pod | 5 ++++- > 4 files changed, 61 insertions(+), 4 deletions(-) > > diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in > index a4e8ca9..1490558 100644 > --- a/include/libvirt/libvirt.h.in > +++ b/include/libvirt/libvirt.h.in > @@ -4490,6 +4490,18 @@ typedef virMemoryParameter *virMemoryParameterPtr; > */ > # define VIR_NODE_MEMORY_SHARED_FULL_SCANS "shm_full_scans" > > +/* VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES: > + * > + * Macro for typed parameter that represents whether pages from > + * different NUMA nodes can be merged. The parameter has type int, > + * when its value is 0, only pages which physically reside in the > + * memory area of same NUMA node are merged; When its value is 1, > + * pages from all nodes can be merged. Other values are reserved > + * for future use. > + */ > +# define VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES "shm_merge_across_nodes" > + > + > int virNodeGetMemoryParameters(virConnectPtr conn, > virTypedParameterPtr params, > int *nparams, > diff --git a/src/nodeinfo.c b/src/nodeinfo.c > index c0e60d8..8f96b8b 100644 > --- a/src/nodeinfo.c > +++ b/src/nodeinfo.c > @@ -1005,6 +1005,8 @@ nodeSetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, > VIR_TYPED_PARAM_UINT, > VIR_NODE_MEMORY_SHARED_SLEEP_MILLISECS, > VIR_TYPED_PARAM_UINT, > + VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES, > + VIR_TYPED_PARAM_UINT, > NULL)< 0) > return -1; > > @@ -1025,6 +1027,13 @@ nodeSetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, > /* Out of memory */ > if (ret == -2) > return -1; > + } else if (STREQ(param->field, > + VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES)) { > + ret = nodeSetMemoryParameterValue("merge_across_nodes", param); > + > + /* Out of memory */ > + if (ret == -2) > + return -1; > } > } > > @@ -1060,8 +1069,9 @@ nodeGetMemoryParameterValue(const char *field, > if ((tmp = strchr(buf, '\n'))) > *tmp = '\0'; > > - if (STREQ(field, "pages_to_scan") || > - STREQ(field, "sleep_millisecs")) > + if (STREQ(field, "pages_to_scan") || > + STREQ(field, "sleep_millisecs") || > + STREQ(field, "merge_across_nodes")) > rc = virStrToLong_ui(buf, NULL, 10, (unsigned int *)value); > else if (STREQ(field, "pages_shared") || > STREQ(field, "pages_sharing") || > @@ -1084,7 +1094,7 @@ cleanup: > } > #endif > > -#define NODE_MEMORY_PARAMETERS_NUM 7 > +#define NODE_MEMORY_PARAMETERS_NUM 8 > int > nodeGetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, > virTypedParameterPtr params ATTRIBUTE_UNUSED, > @@ -1096,6 +1106,7 @@ nodeGetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, > #ifdef __linux__ > unsigned int pages_to_scan; > unsigned int sleep_millisecs; > + unsigned int merge_across_nodes; > unsigned long long pages_shared; > unsigned long long pages_sharing; > unsigned long long pages_unshared; > @@ -1189,6 +1200,17 @@ nodeGetMemoryParameters(virConnectPtr conn ATTRIBUTE_UNUSED, > > break; > > + case 7: > + if (nodeGetMemoryParameterValue("merge_across_nodes", > +&merge_across_nodes)< 0) > + return -1; > + > + if (virTypedParameterAssign(param, VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES, > + VIR_TYPED_PARAM_UINT, merge_across_nodes)< 0) > + return -1; > + > + break; > + > default: > break; > } > diff --git a/tools/virsh-host.c b/tools/virsh-host.c > index 5cf192d..106f5e9 100644 > --- a/tools/virsh-host.c > +++ b/tools/virsh-host.c > @@ -920,6 +920,8 @@ static const vshCmdOptDef opts_node_memory_tune[] = { > {"shm-sleep-millisecs", VSH_OT_INT, VSH_OFLAG_NONE, > N_("number of millisecs the shared memory service should " > "sleep before next scan")}, > + {"shm-merge-across-nodes", VSH_OT_INT, VSH_OFLAG_NONE, > + N_("Specifies if pages from different numa nodes can be merged")}, > {NULL, 0, 0, NULL} > }; > > @@ -931,6 +933,7 @@ cmdNodeMemoryTune(vshControl *ctl, const vshCmd *cmd) > unsigned int flags = 0; > unsigned int shm_pages_to_scan = 0; > unsigned int shm_sleep_millisecs = 0; > + unsigned int shm_merge_across_nodes = 0; > bool ret = false; > int i = 0; > > @@ -946,12 +949,21 @@ cmdNodeMemoryTune(vshControl *ctl, const vshCmd *cmd) > return false; > } > > + if (vshCommandOptUInt(cmd, "shm-merge-across-nodes", > +&shm_merge_across_nodes)< 0) { > + vshError(ctl, "%s", _("invalid shm-merge-across-nodes number")); > + return false; > + } > + > if (shm_pages_to_scan) > nparams++; > > if (shm_sleep_millisecs) > nparams++; > > + if (shm_merge_across_nodes) > + nparams++; > + > if (nparams == 0) { > /* Get the number of memory parameters */ > if (virNodeGetMemoryParameters(ctl->conn, NULL,&nparams, flags) != 0) { > @@ -1003,6 +1015,14 @@ cmdNodeMemoryTune(vshControl *ctl, const vshCmd *cmd) > goto error; > } > > + if (i< nparams&& shm_merge_across_nodes) { > + if (virTypedParameterAssign(&params[i++], > + VIR_NODE_MEMORY_SHARED_MERGE_ACROSS_NODES, > + VIR_TYPED_PARAM_UINT, > + shm_merge_across_nodes)< 0) > + goto error; > + } > + > if (virNodeSetMemoryParameters(ctl->conn, params, nparams, flags) != 0) > goto error; > else > diff --git a/tools/virsh.pod b/tools/virsh.pod > index 2d90b7b..0481e1f 100644 > --- a/tools/virsh.pod > +++ b/tools/virsh.pod > @@ -303,7 +303,10 @@ Allows you to display or set the node memory parameters. > I<shm-pages-to-scan> can be used to set the number of pages to scan > before the shared memory service goes to sleep; I<shm-sleep-millisecs> > can be used to set the number of millisecs the shared memory service should > -sleep before next scan. > +sleep before next scan; I<shm-merge-across-nodes> specifies if pages from > +different numa nodes can be merged. When set to 0, only pages which physically > +reside in the memory area of same NUMA node can be merged. When set to 1, > +pages from all nodes can be merged. Default to 1. > > =item B<capabilities> > Okay, ACK,