Kernel space: no shortage of tracing options
Three weeks ago, LWN looked at the renewed interest in dynamic tracing, with an emphasis on SystemTap. Tracing is a perennial presence on end-user wishlists; it remains a handy tool for companies like Sun Microsystems, which wish to show that their offerings (Solaris, for example) are superior to Linux. It is not surprising that there is a lot of interest in tracing implementations for Linux; the main surprise is that, after all this time, Linux still does not have a top-quality answer to DTrace - though, arguably, Linux had a working tracing mechanism long before DTrace made its appearance.
Even a casual reader of the kernel mailing list will have noticed that there are a lot of tracing-related patches in circulation at the moment. There are so many, in fact, that it is hard to keep track of them all. So this article will take a quick look at the code which has been posted in an attempt to make the various options a bit clearer.
