Re: [PATCH 2/4] virsh: Add keepalive in new vshConnect function

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 07.03.2014 11:49, Martin Kletzander wrote:
Introducing keepalive similarly to Guannan around 2 years ago.  Since
we want to introduce keepalive for every connection, it makes sense to
wrap the connecting function into new virsh one that can deal
keepalive as well.

Function vshConnect() is now used for connecting and keepalive added
in that function (if possible) helps preventing long waits e.g. while
nework goes down during migration.

This patch also adds the options for keepalive tuning into virsh and
fails connecting only when keepalives are explicitly requested and
cannot be set (whether it is due to missing support in connected
driver or remote server).  If not explicitely requested, a debug
message is printed (hence the addition to virsh-optparse test).

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1073506
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=822839

Signed-off-by: Martin Kletzander <mkletzan@xxxxxxxxxx>
---
  tests/virsh-optparse |  3 +-
  tools/virsh-domain.c |  2 +-
  tools/virsh.c        | 77 +++++++++++++++++++++++++++++++++++++++++++++++-----
  tools/virsh.h        |  5 ++++
  4 files changed, 78 insertions(+), 9 deletions(-)

Missing virsh.pod adjustment while you're adding new command line options.


diff --git a/tests/virsh-optparse b/tests/virsh-optparse
index 214ae41..7d4c699 100755
--- a/tests/virsh-optparse
+++ b/tests/virsh-optparse
@@ -1,7 +1,7 @@
  #!/bin/sh
  # Ensure that virsh option parsing doesn't regress

-# Copyright (C) 2011-2012 Red Hat, Inc.
+# Copyright (C) 2011-2012, 2014 Red Hat, Inc.

  # This program is free software: you can redistribute it and/or modify
  # it under the terms of the GNU General Public License as published by
@@ -38,6 +38,7 @@ fi

  cat <<\EOF > exp-out || framework_failure

+Failed to setup keepalive on connection
  setvcpus: <domain> trying as domain NAME
  setvcpus: count(optdata): 2
  setvcpus: domain(optdata): test
diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
index 1d3c5f0..3e989ee 100644
--- a/tools/virsh-domain.c
+++ b/tools/virsh-domain.c
@@ -8781,7 +8781,7 @@ doMigrate(void *opaque)
          virConnectPtr dconn = NULL;
          virDomainPtr ddom = NULL;

-        dconn = virConnectOpenAuth(desturi, virConnectAuthPtrDefault, 0);
+        dconn = vshConnect(ctl, desturi, false);
          if (!dconn)
              goto out;

diff --git a/tools/virsh.c b/tools/virsh.c
index 9b8429f..73c58a5 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -315,6 +315,45 @@ vshCatchDisconnect(virConnectPtr conn ATTRIBUTE_UNUSED,
          disconnected++;
  }

+/* Main Function which should be used for connecting.
+ * This function properly handles keepalive settings. */
+virConnectPtr
+vshConnect(vshControl *ctl, const char *uri, bool readonly)
+{
+    virConnectPtr c = NULL;
+    int interval = 5; /* Default */
+    int count = 6;    /* Default */
+    bool keepalive_forced = false;
+
+    if (ctl->keepalive_interval >= 0) {
+        interval = ctl->keepalive_interval;
+        keepalive_forced = true;
+    }
+    if (ctl->keepalive_count > 0) {
+        count = ctl->keepalive_count;
+        keepalive_forced = true;
+    }

Both interval and count are allowed to be zero. However, setting interval to zero disables keep alive. If count is set to zero, connection is closed automatically after @interval seconds of inactivity. You are allowing the first case (which doesn't make much sense to me - I mean, user requested keepalive, so why allowing zero value?), and disabling the second case - which could make more sense.

Moreover, 'virsh --keepalive-count 0' will not use user specified count but the default value of 6.

+
+    c = virConnectOpenAuth(uri, virConnectAuthPtrDefault,
+                           readonly ? VIR_CONNECT_RO : 0);
+    if (!c)
+        return NULL;
+
+    if (virConnectSetKeepAlive(c, interval, count) != 0) {
+        if (keepalive_forced) {
+            vshError(ctl, "%s",
+                     _("Cannot setup keepalive on connection "
+                       "as requested, disconnecting"));
+            virConnectClose(c);
+            return NULL;
+        }
+        vshDebug(ctl, VSH_ERR_INFO, "%s",
+                 _("Failed to setup keepalive on connection\n"));
+    }
+
+    return c;
+}
+

Michal

--
libvir-list mailing list
libvir-list@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/libvir-list




[Index of Archives]     [Virt Tools]     [Libvirt Users]     [Lib OS Info]     [Fedora Users]     [Fedora Desktop]     [Fedora SELinux]     [Big List of Linux Books]     [Yosemite News]     [KDE Users]     [Fedora Tools]