# HG changeset patch
# User Matt Mackall <mpm@selenic.com>
# Date 1440440683 18000
# Node ID 3b6e5914edd87b399f24d53d95785d34808f29b2
# Parent  83c9edcac05c51c32283d741c44454a7b7073f63
lock: loop a finite number of times in trylock (issue4787)

..before falling back to lock, which will sleep. This only addresses
the CPU consumption of the reported issue.

diff -r 83c9edcac05c -r 3b6e5914edd8 mercurial/lock.py
--- a/mercurial/lock.py	Fri Aug 14 12:25:14 2015 +0900
+++ b/mercurial/lock.py	Mon Aug 24 13:24:43 2015 -0500
@@ -83,7 +83,9 @@
         if lock._host is None:
             lock._host = socket.gethostname()
         lockname = '%s:%s' % (lock._host, self.pid)
-        while not self.held:
+        retry = 5
+        while not self.held and retry:
+            retry -= 1
             try:
                 self.vfs.makelock(lockname, self.f)
                 self.held = 1