We're experiencing performance issues on our website, and after reviewing our
munin graphs, the only metrics we've found in sync are
Available entropy and
MySQL slow queries, with the latter influenced by our number of logged in users:
Based on the wikipedia entropy page, my understanding is that entropy is the amount of randomness (here measured in bytes) that the system can use for various tasks, mainly cryptography and functions that require random input.
Since the peaks in
available entropy and
MySQL slow queries are occurring in sync and at regular interval, that the number of
MySQL slow queries is proportional to our number of
Drupal users whereas the peaks in
available entropy seem to be much more constant and less proportional to these 2 metrics, we're thinking
available entropy is the reflect of a root cause which, combined with the traffic to our website, is causing those slow queries (and not the opposite, slow queries influencing the entropy). Accordingly:
Q: What underlying problem do you think could cause regular peaks in available entropy that could have an influence on MySQL's ability to process queries?