ivring driver
Hi Yoshihiro,
I stumbled on your post on ivring (https://lkml.org/lkml/2012/6/5/143)
for buffering trace data from guest to host. I notice that it would be very interesting to see a comparison of its performance against:
- ftrace ring buffer
- perf ring buffer
- lttng 2.0 ring buffer
- lttng-ust 2.0 (user-space tracing) ring buffer
Comparing only with network-related mechanisms does not seem to provide a complete picture of where it stands wrt other ring buffers out there.
One of the metric we have used in the past is the number of nanoseconds it takes to write a single event, based on a test that writes lots of events into various buffer sizes, into flight recorder mode buffers (which overwrites oldest information on buffer full condition, with data collection to disk disabled, to remove I/O from the picture -- I/O can then be performed in "snapshot" mode, after some error condition is detected).
Best regards,
Mathieu
Signature · 4 lines
Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com
Quoted 10 lines · Mathieu Desnoyers
Hi Yoshihiro,
I stumbled on your post on ivring (https://lkml.org/lkml/2012/6/5/143)
for buffering trace data from guest to host. I notice that it would be very interesting to see a comparison of its performance against:- ftrace ring buffer
- perf ring buffer
- lttng 2.0 ring buffer
- lttng-ust 2.0 (user-space tracing) ring buffer
Hi Mathieu. Thank you for commenting on how to compare among ring-buffer's performances. And sorry, I'm late for replying to you.
Quoted 10 lines
Comparing only with network-related mechanisms does not seem to provide a complete picture of where it stands wrt other ring buffers out there.
One of the metric we have used in the past is the number of nanoseconds it takes to write a single event, based on a test that writes lots of events into various buffer sizes, into flight recorder mode buffers (which overwrites oldest information on buffer full condition, with data collection to disk disabled, to remove I/O from the picture -- I/O can then be performed in "snapshot" mode, after some error condition is detected).
OK, I see. When the overhead of ring-buffers will be evaluated in the next, I may use the metric as a reference.
Thank you,
Signature · 4 lines
Yoshihiro YUNOMAE Software Platform Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: [email protected]