On 1/23/23 18:18, kyle Hailey wrote:
None of the open source databases is instrumented as well as Oracle. Jeff Holt suggested something on the PostgreSQL list, but was put in his place in a rather rude response. Both MySQL and PostgreSQL are good for small databases, not exceeding 10 TB. If you have a 100TB monster, than Oracle, Snowflake or SQL Server are your only choices.There are also commercial PostgreSQL derivatives, like EDB, Yugabyte and CockroachDB which all look promising. Frits Hoogland, who has recently written a nice article on this list about Oracle to Postgres comparison, works for Yugabyte and that instills confidence in me, more than the actual name. The prefix "Yuga" is a part of the recent history in my country of origin and that _*does not*_ instill confidence.
Anyone tried to use wait events on MySQL?
Looking across a large fleet of MySQL, 70% of the wait time is on wait/io/table/sql/handler.
The event wait/io/table/sql/handler can be CPU, IO and lock!
Seems like waits are pretty useless.
We captured them in RDS and are currently doing so at Datadog, but thinking might even be worth skipping their collections and just reporting MySQL state instead of waits.
Seems incredible that row level locks are not instrumented as their own waits. (Looks like we can deduce lock in rather unsatisfying way TBD)
