https://svn.boost.org/trac10/ticket/4205 <p> OS: Windows Server 2003 </p> <p> In the windows code for run_one, we are seeing excessive CPU when using timers. We didn't see this issue with 1.40. </p> <p> The problem turns out to be that when we have timers, the computation for timeout (via get_timeout()), is too small. Thus the IOCP query returns and no timers are delivered. This leads to a flurry of CPU usage where the timeout is zero and no timers are still delivered. The CPU usage stops when the next pending timer is finally delivered. </p> <p> To resolve the issue (a total temporary hack to our code), we added a bias of 1ms to the call to get_timeout(). (i.e. timeout = get_timeout() + 1;). This caused the CPU usage to drop back down to normal levels. </p> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/4205 Trac 1.4.3 Tim Smith <tim@…> Tue, 11 May 2010 17:17:36 GMT https://svn.boost.org/trac10/ticket/4205#comment:1 https://svn.boost.org/trac10/ticket/4205#comment:1 <ul> <li><strong>version</strong> <span class="trac-field-old">Boost 1.44.0</span> → <span class="trac-field-new">Boost 1.43.0</span> </li> </ul> Ticket chris_kohlhoff Sun, 06 Jun 2010 23:29:02 GMT https://svn.boost.org/trac10/ticket/4205#comment:2 https://svn.boost.org/trac10/ticket/4205#comment:2 <ul> <li><strong>status</strong> <span class="trac-field-old">new</span> → <span class="trac-field-new">closed</span> </li> <li><strong>resolution</strong> → <span class="trac-field-new">fixed</span> </li> </ul> <p> (In <a class="changeset" href="https://svn.boost.org/trac10/changeset/62497" title="Fix handling of small but non-zero timeouts. Fixes #4205. ">[62497]</a>) Fix handling of small but non-zero timeouts. Fixes <a class="closed ticket" href="https://svn.boost.org/trac10/ticket/4205" title="#4205: Bugs: Excessive CPU using in run_one in ASIO (closed: fixed)">#4205</a>. </p> Ticket chris_kohlhoff Wed, 09 Jun 2010 09:41:14 GMT