From: Ben Pfaff Date: Wed, 22 Sep 2010 23:45:30 +0000 (-0700) Subject: ovs-vswitchd: Export system stats through Open_vSwitch table. X-Git-Tag: v1.1.0~1082 X-Git-Url: http://git.onelab.eu/?p=sliver-openvswitch.git;a=commitdiff_plain;h=ce8876775477a359f3ae14b8cae0ef2212f1681b ovs-vswitchd: Export system stats through Open_vSwitch table. This is intended to provide controllers enough information to determine whether a switch is overloaded or busted, to enable them to spread load fairly across a group of switches. Feature #2421. CC: Peter Balland --- diff --git a/PORTING b/PORTING index 5f88c940a..922d6c85b 100644 --- a/PORTING +++ b/PORTING @@ -209,6 +209,9 @@ lib/entropy.c assumes that it can obtain high-quality random number seeds at startup by reading from /dev/urandom. You will need to modify it if this is not true on your platform. +vswitchd/system-stats.c only knows how to obtain some statistics on +Linux. Optionally you may implement them for your platform as well. + Questions --------- diff --git a/configure.ac b/configure.ac index 08a6f0fdf..8a5dc5ce0 100644 --- a/configure.ac +++ b/configure.ac @@ -55,7 +55,8 @@ OVS_CHECK_IF_PACKET OVS_CHECK_STRTOK_R AC_CHECK_MEMBERS([struct stat.st_mtim.tv_nsec, struct stat.st_mtimensec], [], [], [[#include ]]) -AC_CHECK_FUNCS([mlockall]) +AC_CHECK_FUNCS([mlockall strsignal getloadavg statvfs setmntent]) +AC_CHECK_HEADERS([mntent.h sys/statvfs.h]) OVS_CHECK_PKIDIR OVS_CHECK_RUNDIR @@ -64,8 +65,6 @@ OVS_CHECK_VALGRIND OVS_CHECK_SOCKET_LIBS OVS_CHECK_LINKER_SECTIONS -AC_CHECK_FUNCS([strsignal]) - OVS_ENABLE_OPTION([-Wall]) OVS_ENABLE_OPTION([-Wno-sign-compare]) OVS_ENABLE_OPTION([-Wpointer-arith]) diff --git a/lib/vlog-modules.def b/lib/vlog-modules.def index 03f310375..7d614b412 100644 --- a/lib/vlog-modules.def +++ b/lib/vlog-modules.def @@ -78,6 +78,7 @@ VLOG_MODULE(status) VLOG_MODULE(svec) VLOG_MODULE(timeval) VLOG_MODULE(socket_util) +VLOG_MODULE(system_stats) VLOG_MODULE(unixctl) VLOG_MODULE(util) VLOG_MODULE(vconn_stream) diff --git a/vswitchd/automake.mk b/vswitchd/automake.mk index 592be607a..1a4b465f5 100644 --- a/vswitchd/automake.mk +++ b/vswitchd/automake.mk @@ -12,6 +12,7 @@ vswitchd_ovs_vswitchd_SOURCES = \ vswitchd/proc-net-compat.c \ vswitchd/proc-net-compat.h \ vswitchd/ovs-vswitchd.c \ + vswitchd/system-stats.c \ vswitchd/vswitch-idl.c \ vswitchd/vswitch-idl.h \ vswitchd/xenserver.c \ diff --git a/vswitchd/bridge.c b/vswitchd/bridge.c index 3f5e3d471..77eb152ce 100644 --- a/vswitchd/bridge.c +++ b/vswitchd/bridge.c @@ -57,6 +57,7 @@ #include "socket-util.h" #include "stream-ssl.h" #include "svec.h" +#include "system-stats.h" #include "timeval.h" #include "util.h" #include "unixctl.h" @@ -1096,6 +1097,20 @@ iface_refresh_stats(struct iface *iface) ovsrec_interface_set_statistics(iface->cfg, keys, values, n); } +static void +refresh_system_stats(const struct ovsrec_open_vswitch *cfg) +{ + struct ovsdb_datum datum; + struct shash stats; + + shash_init(&stats); + get_system_stats(&stats); + + ovsdb_datum_from_shash(&datum, &stats); + ovsdb_idl_txn_write(&cfg->header_, &ovsrec_open_vswitch_col_statistics, + &datum); +} + void bridge_run(void) { @@ -1153,24 +1168,27 @@ bridge_run(void) /* Refresh interface stats if necessary. */ if (time_msec() >= iface_stats_timer) { - struct ovsdb_idl_txn *txn; + if (cfg) { + struct ovsdb_idl_txn *txn; - txn = ovsdb_idl_txn_create(idl); - LIST_FOR_EACH (br, struct bridge, node, &all_bridges) { - size_t i; + txn = ovsdb_idl_txn_create(idl); + LIST_FOR_EACH (br, struct bridge, node, &all_bridges) { + size_t i; - for (i = 0; i < br->n_ports; i++) { - struct port *port = br->ports[i]; - size_t j; + for (i = 0; i < br->n_ports; i++) { + struct port *port = br->ports[i]; + size_t j; - for (j = 0; j < port->n_ifaces; j++) { - struct iface *iface = port->ifaces[j]; - iface_refresh_stats(iface); + for (j = 0; j < port->n_ifaces; j++) { + struct iface *iface = port->ifaces[j]; + iface_refresh_stats(iface); + } } } + refresh_system_stats(cfg); + ovsdb_idl_txn_commit(txn); + ovsdb_idl_txn_destroy(txn); /* XXX */ } - ovsdb_idl_txn_commit(txn); - ovsdb_idl_txn_destroy(txn); /* XXX */ iface_stats_timer = time_msec() + IFACE_STATS_INTERVAL; } diff --git a/vswitchd/system-stats.c b/vswitchd/system-stats.c new file mode 100644 index 000000000..11b2fbedb --- /dev/null +++ b/vswitchd/system-stats.c @@ -0,0 +1,503 @@ +/* Copyright (c) 2010 Nicira Networks + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include + +#include +#include +#include +#include +#if HAVE_MNTENT_H +#include +#endif +#include +#include +#include +#include +#if HAVE_SYS_STATVFS_H +#include +#endif +#include + +#include "daemon.h" +#include "dirs.h" +#include "dynamic-string.h" +#include "shash.h" +#include "system-stats.h" +#include "timeval.h" +#include "vlog.h" + +VLOG_DEFINE_THIS_MODULE(system_stats) + +/* #ifdefs make it a pain to maintain code: you have to try to build both ways. + * Thus, this file tries to compile as much of the code as possible regardless + * of the target, by writing "if (LINUX)" instead of "#ifdef __linux__" where + * this is possible. */ +#ifdef __linux__ +#include +#define LINUX 1 +#else +#define LINUX 0 +#endif + +static void +get_cpu_cores(struct shash *stats) +{ + long int n_cores = sysconf(_SC_NPROCESSORS_ONLN); + if (n_cores > 0) { + shash_add(stats, "cpu", xasprintf("%ld", n_cores)); + } +} + +static void +get_load_average(struct shash *stats OVS_UNUSED) +{ +#if HAVE_GETLOADAVG + double loadavg[3]; + + if (getloadavg(loadavg, 3) == 3) { + shash_add(stats, "load_average", + xasprintf("%.2f,%.2f,%.2f", + loadavg[0], loadavg[1], loadavg[2])); + } +#endif +} + +static unsigned int +get_page_size(void) +{ + static unsigned int cached; + + if (!cached) { + long int value = sysconf(_SC_PAGESIZE); + if (value >= 0) { + cached = value; + } + } + + return cached; +} + +static void +get_memory_stats(struct shash *stats) +{ + if (!LINUX) { + unsigned int pagesize = get_page_size(); + long int phys_pages = sysconf(_SC_PHYS_PAGES); + long int avphys_pages = sysconf(_SC_AVPHYS_PAGES); + int mem_total, mem_used; + + if (pagesize <= 0 || phys_pages <= 0 || avphys_pages <= 0) { + return; + } + + mem_total = phys_pages * (pagesize / 1024); + mem_used = (phys_pages - avphys_pages) * (pagesize / 1024); + shash_add(stats, "memory", xasprintf("%d,%d", mem_total, mem_used)); + } else { + static const char file_name[] = "/proc/meminfo"; + int mem_used, mem_cache, swap_used; + int mem_free = 0; + int buffers = 0; + int cached = 0; + int swap_free = 0; + int mem_total = 0; + int swap_total = 0; + struct shash dict; + char line[128]; + FILE *stream; + + stream = fopen(file_name, "r"); + if (!stream) { + VLOG_WARN_ONCE("%s: open failed (%s)", file_name, strerror(errno)); + return; + } + + shash_init(&dict); + shash_add(&dict, "MemTotal", &mem_total); + shash_add(&dict, "MemFree", &mem_free); + shash_add(&dict, "Buffers", &buffers); + shash_add(&dict, "Cached", &cached); + shash_add(&dict, "SwapTotal", &swap_total); + shash_add(&dict, "SwapFree", &swap_free); + while (fgets(line, sizeof line, stream)) { + char key[16]; + int value; + + if (sscanf(line, "%15[^:]: %u", key, &value) == 2) { + int *valuep = shash_find_data(&dict, key); + if (valuep) { + *valuep = value; + } + } + } + fclose(stream); + shash_destroy(&dict); + + mem_used = mem_total - mem_free; + mem_cache = buffers + cached; + swap_used = swap_total - swap_free; + shash_add(stats, "memory", + xasprintf("%d,%d,%d,%d,%d", mem_total, mem_used, mem_cache, + swap_total, swap_used)); + } +} + +/* Returns the time at which the system booted, as the number of milliseconds + * since the epoch, or 0 if the time of boot cannot be determined. */ +static long long int +get_boot_time(void) +{ + static long long int cache_expiration = LLONG_MIN; + static long long int boot_time; + + assert(LINUX); + + if (time_msec() >= cache_expiration) { + static const char stat_file[] = "/proc/stat"; + char line[128]; + FILE *stream; + + cache_expiration = time_msec() + 5 * 1000; + + stream = fopen(stat_file, "r"); + if (!stream) { + VLOG_ERR_ONCE("%s: open failed (%s)", stat_file, strerror(errno)); + return boot_time; + } + + while (fgets(line, sizeof line, stream)) { + long long int btime; + if (sscanf(line, "btime %lld", &btime) == 1) { + boot_time = btime * 1000; + goto done; + } + } + VLOG_ERR_ONCE("%s: btime not found", stat_file); + done: + fclose(stream); + } + return boot_time; +} + +static unsigned long long int +ticks_to_ms(unsigned long long int ticks) +{ + assert(LINUX); + +#ifndef USER_HZ +#define USER_HZ 100 +#endif + +#if USER_HZ == 100 /* Common case. */ + return ticks * (1000 / USER_HZ); +#else /* Alpha and some other architectures. */ + double factor = 1000.0 / USER_HZ; + return ticks * factor + 0.5; +#endif +} + +struct raw_process_info { + unsigned long int vsz; /* Virtual size, in kB. */ + unsigned long int rss; /* Resident set size, in kB. */ + long long int uptime; /* ms since started. */ + long long int cputime; /* ms of CPU used during 'uptime'. */ + pid_t ppid; /* Parent. */ + char name[18]; /* Name (surrounded by parentheses). */ +}; + +static bool +get_raw_process_info(pid_t pid, struct raw_process_info *raw) +{ + unsigned long long int vsize, rss, start_time, utime, stime; + long long int start_msec; + unsigned long ppid; + char file_name[128]; + FILE *stream; + int n; + + assert(LINUX); + + sprintf(file_name, "/proc/%lu/stat", (unsigned long int) pid); + stream = fopen(file_name, "r"); + if (!stream) { + VLOG_ERR_ONCE("%s: open failed (%s)", file_name, strerror(errno)); + return false; + } + + n = fscanf(stream, + "%*d " /* (1. pid) */ + "%17s " /* 2. process name */ + "%*c " /* (3. state) */ + "%lu " /* 4. ppid */ + "%*d " /* (5. pgid) */ + "%*d " /* (6. sid) */ + "%*d " /* (7. tty_nr) */ + "%*d " /* (8. tty_pgrp) */ + "%*u " /* (9. flags) */ + "%*u " /* (10. min_flt) */ + "%*u " /* (11. cmin_flt) */ + "%*u " /* (12. maj_flt) */ + "%*u " /* (13. cmaj_flt) */ + "%llu " /* 14. utime */ + "%llu " /* 15. stime */ + "%*d " /* (16. cutime) */ + "%*d " /* (17. cstime) */ + "%*d " /* (18. priority) */ + "%*d " /* (19. nice) */ + "%*d " /* (20. num_threads) */ + "%*d " /* (21. always 0) */ + "%llu " /* 22. start_time */ + "%llu " /* 23. vsize */ + "%llu " /* 24. rss */ +#if 0 + /* These are here for documentation but #if'd out to save + * actually parsing them from the stream for no benefit. */ + "%*lu " /* (25. rsslim) */ + "%*lu " /* (26. start_code) */ + "%*lu " /* (27. end_code) */ + "%*lu " /* (28. start_stack) */ + "%*lu " /* (29. esp) */ + "%*lu " /* (30. eip) */ + "%*lu " /* (31. pending signals) */ + "%*lu " /* (32. blocked signals) */ + "%*lu " /* (33. ignored signals) */ + "%*lu " /* (34. caught signals) */ + "%*lu " /* (35. whcan) */ + "%*lu " /* (36. always 0) */ + "%*lu " /* (37. always 0) */ + "%*d " /* (38. exit_signal) */ + "%*d " /* (39. task_cpu) */ + "%*u " /* (40. rt_priority) */ + "%*u " /* (41. policy) */ + "%*llu " /* (42. blkio_ticks) */ + "%*lu " /* (43. gtime) */ + "%*ld" /* (44. cgtime) */ +#endif + , raw->name, &ppid, &utime, &stime, &start_time, &vsize, &rss); + fclose(stream); + if (n != 7) { + VLOG_ERR_ONCE("%s: fscanf failed", file_name); + return false; + } + + start_msec = get_boot_time() + ticks_to_ms(start_time); + + raw->vsz = vsize / 1024; + raw->rss = rss * (getpagesize() / 1024); + raw->uptime = time_wall_msec() - start_msec; + raw->cputime = ticks_to_ms(utime + stime); + raw->ppid = ppid; + + return true; +} + +static int +count_crashes(pid_t pid) +{ + char file_name[128]; + const char *paren; + char line[128]; + int crashes = 0; + FILE *stream; + + assert(LINUX); + + sprintf(file_name, "/proc/%lu/cmdline", (unsigned long int) pid); + stream = fopen(file_name, "r"); + if (!stream) { + VLOG_WARN_ONCE("%s: open failed (%s)", file_name, strerror(errno)); + goto exit; + } + + if (!fgets(line, sizeof line, stream)) { + VLOG_WARN_ONCE("%s: read failed (%s)", file_name, + feof(stream) ? "end of file" : strerror(errno)); + goto exit_close; + } + + paren = strchr(line, '('); + if (paren) { + int x; + if (sscanf(paren + 1, "%d", &x) == 1) { + crashes = x; + } + } + +exit_close: + fclose(stream); +exit: + return crashes; +} + +struct process_info { + unsigned long int vsz; /* Virtual size, in kB. */ + unsigned long int rss; /* Resident set size, in kB. */ + long long int booted; /* ms since monitor started. */ + int crashes; /* # of crashes (usually 0). */ + long long int uptime; /* ms since last (re)started by monitor. */ + long long int cputime; /* ms of CPU used during 'uptime'. */ +}; + +static bool +get_process_info(pid_t pid, struct process_info *pinfo) +{ + struct raw_process_info child; + + assert(LINUX); + if (!get_raw_process_info(pid, &child)) { + return false; + } + + pinfo->vsz = child.vsz; + pinfo->rss = child.rss; + pinfo->booted = child.uptime; + pinfo->crashes = 0; + pinfo->uptime = child.uptime; + pinfo->cputime = child.cputime; + + if (child.ppid) { + struct raw_process_info parent; + + get_raw_process_info(child.ppid, &parent); + if (!strcmp(child.name, parent.name)) { + pinfo->booted = parent.uptime; + pinfo->crashes = count_crashes(child.ppid); + } + } + + return true; +} + +static void +get_process_stats(struct shash *stats) +{ + struct dirent *de; + DIR *dir; + + dir = opendir(ovs_rundir); + if (!dir) { + VLOG_ERR_ONCE("%s: open failed (%s)", ovs_rundir, strerror(errno)); + return; + } + + while ((de = readdir(dir)) != NULL) { + struct process_info pinfo; + char *key, *value; + char *file_name; + char *extension; + pid_t pid; + +#ifdef _DIRENT_HAVE_D_TYPE + if (de->d_type != DT_UNKNOWN && de->d_type != DT_REG) { + continue; + } +#endif + + extension = strrchr(de->d_name, '.'); + if (!extension || strcmp(extension, ".pid")) { + continue; + } + + file_name = xasprintf("%s/%s", ovs_rundir, de->d_name); + pid = read_pidfile(file_name); + free(file_name); + if (pid < 0 || kill(pid, 0)) { + continue; + } + + key = xasprintf("process_%.*s", + (int) (extension - de->d_name), de->d_name); + if (shash_find(stats, key)) { + free(key); + continue; + } + + if (LINUX && get_process_info(pid, &pinfo)) { + value = xasprintf("%lu,%lu,%lld,%d,%lld,%lld", + pinfo.vsz, pinfo.rss, pinfo.cputime, + pinfo.crashes, pinfo.booted, pinfo.uptime); + } else { + value = xstrdup(""); + } + + shash_add_nocopy(stats, key, value); + } + + closedir(dir); +} + +static void +get_filesys_stats(struct shash *stats OVS_UNUSED) +{ +#if HAVE_SETMNTENT && HAVE_STATVFS + static const char file_name[] = "/etc/mtab"; + struct mntent *me; + FILE *stream; + struct ds s; + + stream = setmntent(file_name, "r"); + if (!stream) { + VLOG_ERR_ONCE("%s: open failed (%s)", file_name, strerror(errno)); + return; + } + + ds_init(&s); + while ((me = getmntent(stream)) != NULL) { + unsigned long long int total, free; + struct statvfs vfs; + char *p; + + /* Skip non-local and read-only filesystems. */ + if (strncmp(me->mnt_fsname, "/dev", 4) + || !strstr(me->mnt_opts, "rw")) { + continue; + } + + /* Given the mount point we can stat the file system. */ + if (statvfs(me->mnt_dir, &vfs) && vfs.f_flag & ST_RDONLY) { + /* That's odd... */ + continue; + } + + /* Now format the data. */ + if (s.length) { + ds_put_char(&s, ' '); + } + for (p = me->mnt_dir; *p != '\0'; p++) { + ds_put_char(&s, *p == ' ' || *p == ',' ? '_' : *p); + } + total = (unsigned long long int) vfs.f_frsize * vfs.f_blocks / 1024; + free = (unsigned long long int) vfs.f_frsize * vfs.f_bfree / 1024; + ds_put_format(&s, ",%llu,%llu", total, total - free); + } + endmntent(stream); + + if (s.length) { + shash_add(stats, "file_systems", ds_steal_cstr(&s)); + } + ds_destroy(&s); +#endif /* HAVE_SETMNTENT && HAVE_STATVFS */ +} + +void +get_system_stats(struct shash *stats) +{ + get_cpu_cores(stats); + get_load_average(stats); + get_memory_stats(stats); + get_process_stats(stats); + get_filesys_stats(stats); +} diff --git a/vswitchd/system-stats.h b/vswitchd/system-stats.h new file mode 100644 index 000000000..559be692d --- /dev/null +++ b/vswitchd/system-stats.h @@ -0,0 +1,21 @@ +/* Copyright (c) 2010 Nicira Networks + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef VSWITCHD_SYSTEM_STATS +#define VSWITCHD_SYSTEM_STATS 1 + +void get_system_stats(struct shash *); + +#endif /* vswitchd/system-stats.h */ diff --git a/vswitchd/vswitch.ovsschema b/vswitchd/vswitch.ovsschema index 07dd79fbc..d872fdc51 100644 --- a/vswitchd/vswitch.ovsschema +++ b/vswitchd/vswitch.ovsschema @@ -25,7 +25,7 @@ "refTable": "Capability"}, "min": 0, "max": "unlimited"}}, "statistics": { - "type": {"key": "string", "value": "integer", "min": 0, "max": "unlimited"}, + "type": {"key": "string", "value": "string", "min": 0, "max": "unlimited"}, "ephemeral": true}}, "maxRows": 1}, "Capability": { diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml index bb3f648fb..141c5fe53 100644 --- a/vswitchd/vswitch.xml +++ b/vswitchd/vswitch.xml @@ -1,3 +1,4 @@ +

A database with this schema holds the configuration for one Open vSwitch daemon. The root of the configuration for the daemon is @@ -74,21 +75,133 @@

- Key-value pairs that report statistics about a running Open_vSwitch - daemon. The current implementation updates these counters - periodically. In the future, we plan to, instead, update them only - when they are queried (e.g. using an OVSDB select - operation) and perhaps at other times, but not on any regular - periodic basis.

-

- The currently defined key-value pairs are listed below. Some Open - vSwitch implementations may not support some statistics, in which - case those key-value pairs are omitted.

+ Key-value pairs that report statistics about a system running an Open + vSwitch. These are updated periodically (currently, every 5 + seconds). Key-value pairs that cannot be determined or that do not + apply to a platform are omitted. +

+
-
load-average
+
cpu
+
+

+ Number of CPU processors, threads, or cores currently online and + available to the operating system on which Open vSwitch is + running, as an integer. This may be less than the number + installed, if some are not online or if they are not available to + the operating system. +

+

+ Open vSwitch userspace processes are not multithreaded, but the + Linux kernel-based datapath is. +

+
+ +
load_average
+
+

+ A comma-separated list of three floating-point numbers, + representing the system load average over the last 1, 5, and 15 + minutes, respectively. +

+
+ +
memory
+
+

+ A comma-separated list of integers, each of which represents a + quantity of memory in kilobytes that describes the operating + system on which Open vSwitch is running. In respective order, + these values are: +

+ +
    +
  1. Total amount of RAM allocated to the OS.
    2. +
  2. RAM allocated to the OS that is in use.
    3. +
  3. RAM that can be flushed out to disk or otherwise discarded + if that space is needed for another purpose. This number is + necessarily less than or equal to the previous value.
    4. +
  4. Total disk space allocated for swap.
    5. +
  5. Swap space currently in use.
    6. +
+ +

+ On Linux, all five values can be determined and are included. On + other operating systems, only the first two values can be + determined, so the list will only have two values. +

+
+ +
process_name
- System load average multiplied by 100 and rounded to the nearest - integer.
+

+ One such key-value pair will exist for each running Open vSwitch + daemon process, with name replaced by the daemon's + name (e.g. process_ovs-vswitchd). The value is a + comma-separated list of integers. The integers represent the + following, with memory measured in kilobytes and durations in + milliseconds: +

+ +
    +
  1. The process's virtual memory size.
    2. +
  2. The process's resident set size.
    3. +
  3. The amount of user and system CPU time consumed by the + process.
    4. +
  4. The number of times that the process has crashed and been + automatically restarted by the monitor.
    5. +
  5. The duration since the process was started.
    6. +
  6. The duration for which the process has been running.
    7. +
+ +

+ The interpretation of some of these values depends on whether the + process was started with the . If it + was not, then the crash count will always be 0 and the two + durations will always be the same. If + was given, then the crash count may be positive; if it is, the + latter duration is the amount of time since the most recent crash + and restart. +

+ +

+ There will be one key-value pair for each file in Open vSwitch's + ``run directory'' (usually /var/run/openvswitch) + whose name ends in .pid, whose contents are a + process ID, and which is locked by a running process. The + name is taken from the pidfile's name. +

+ +

+ Currently Open vSwitch is only able to obtain all of the above + detail on Linux systems. On other systems, the same key-value + pairs will be present but the values will always be the empty + string. +

+ + +
file_systems
+
+

+ A space-separated list of information on local, writable file + systems. Each item in the list describes one file system and + consists in turn of a comma-separated list of the following: +

+ +
    +
  1. Mount point, e.g. / or /var/log. + Any spaces or commas in the mount point are replaced by + underscores.
    2. +
  2. Total size, in kilobytes, as an integer.
    3. +
  3. Amount of storage in use, in kilobytes, as an integer.
    4. +
+ +

+ This key-value pair is omitted if there are no local, writable + file systems or if Open vSwitch cannot obtain the needed + information. +

+