DTrace OEL Dynamic Language Support

Posted by Adam Leventhal on

We built DTrace to solve problems; at the start, the problems we understood best were our own. In the Solaris Kernel Group we started by instrumenting the kernel and system calls, the user/kernel boundary. Early use required detailed knowledge of kernel internals. As DTrace use grew—within the team, in Sun and then beyond—we extended DTrace […]

Read More

Tuning the OpenZFS write throttle

Posted by Adam Leventhal on

In previous posts I discussed the problems with the legacy ZFS write throttle that cause degraded performance and wildly variable latencies. I then presented the new OpenZFS write throttle and I/O scheduler that Matt Ahrens and I designed. In addition to solving several problems in ZFS, the new approach was designed to be easy to […]

Read More

The case of the un-unmountable tmpfs

Posted by Adam Leventhal on

Every once in a rare while our development machines encounter an fatal error during boot because we couldn’t unmount tmpfs. This weekend I cracked the case, so I thought I’d share my uses of boot-time DTrace, and the musty corners of the operating systems that I encountered along the way. First I should explain a…

Read More

Welcome Matt Amdur

Posted by Adam Leventhal on

It’s my pleasure to welcome Matt Amdur to Delphix, to the world of DTrace, and — just today — to the blogosphere. Matt joined¬†Delphix about two months after 10 years of software engineering, most recently at VMware. Matt and I met in at Brown University in 1997 where we worked together closely for all four…

Read More

DTrace for Linux

Posted by Adam Leventhal on

Yesterday (October 4, 2011) Oracle made the surprising announcement that they would be porting some key Solaris features, DTrace and Zones, to Oracle Enterprise Linux. As one of the original authors, the news about DTrace was particularly interesting to me, so I started digging. I should note that this isn’t the¬†first time I’ve written about…

Read More