Re: [PATCH 0/7] Share events between metrics

On Wed, May 20, 2020 at 12:28:07AM -0700, Ian Rogers wrote:

Metric groups contain metrics. Metrics create groups of events to
ideally be scheduled together. Often metrics refer to the same events,
for example, a cache hit and cache miss rate. Using separate event
groups means these metrics are multiplexed at different times and the
counts don't sum to 100%. More multiplexing also decreases the
accuracy of the measurement.

This change orders metrics from groups or the command line, so that
the ones with the most events are set up first. Later metrics see if
groups already provide their events, and reuse them if
possible. Unnecessary events and groups are eliminated.

The option --metric-no-group is added so that metrics aren't placed in
groups. This affects multiplexing and may increase sharing.

The option --metric-mo-merge is added and with this option the
existing grouping behavior is preserved.

Using skylakex metrics I ran the following shell code to count the
number of events for each metric group (this ignores metric groups
with a single metric, and one of the duplicated TopdownL1 and
TopDownL1 groups):

hi,
I'm getting parser error with:

[jolsa@krava perf]$ sudo ./perf stat -M IPC,CPI -a -I 1000
event syntax error: '..ed.thread}:W{inst_retired.any,cpu_clk_unhalted.thread}:W,{inst_retired.any,cycles}:W'
                                  \___ parser error


jirka