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-rwxr-xr-xscripts/kvm/kvm_stat29
1 files changed, 28 insertions, 1 deletions
diff --git a/scripts/kvm/kvm_stat b/scripts/kvm/kvm_stat
index 25631a49f7..d43e8f3e85 100755
--- a/scripts/kvm/kvm_stat
+++ b/scripts/kvm/kvm_stat
@@ -705,7 +705,34 @@ def log(stats):
line += 1
def get_options():
- optparser = optparse.OptionParser()
+ description_text = """
+This script displays various statistics about VMs running under KVM.
+The statistics are gathered from the KVM debugfs entries and / or the
+currently available perf traces.
+
+The monitoring takes additional cpu cycles and might affect the VM's
+performance.
+
+Requirements:
+- Access to:
+ /sys/kernel/debug/kvm
+ /sys/kernel/debug/trace/events/*
+ /proc/pid/task
+- /proc/sys/kernel/perf_event_paranoid < 1 if user has no
+ CAP_SYS_ADMIN and perf events are used.
+- CAP_SYS_RESOURCE if the hard limit is not high enough to allow
+ the large number of files that are possibly opened.
+"""
+
+ class PlainHelpFormatter(optparse.IndentedHelpFormatter):
+ def format_description(self, description):
+ if description:
+ return description + "\n"
+ else:
+ return ""
+
+ optparser = optparse.OptionParser(description=description_text,
+ formatter=PlainHelpFormatter())
optparser.add_option('-1', '--once', '--batch',
action='store_true',
default=False,