On 08/25/2016 11:21 AM, Avi Kivity wrote:
Hi,
Should I wait for ongoing improvement here, or shall I look elsewhere
for my tracing needs?
It would be a pity (for me) if I have to find another solution, because
systemtap has all the expressiveness and integration I need. But it has
a dramatic impact on my application runtime.
I was able to extract some useful data with perf probe/perf record, but
as soon as I need to qualify a probe point with runtime information,
perf falls short.
As Frank mentioned in a previous email, it might be possible for us to
switch to using straight kprobes instead of syscall tracing to handle
mmap tracing. In your use case of calling epoll_wait() lots of times per
second, that might be a *big* win.
I'll see what can be done to add that feature.