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tatut 2021-03-23T08:50:19.087900Z

is there an easy way to restart query group nodes without redeploying ions? I have some things nodes do on startup that I’d like them to redo

tatut 2021-03-24T08:26:26.091400Z

good to know… not a problem here as this is a temporary measure for something that happens rarely

tatut 2021-03-23T09:05:55.088Z

it seems AWS autoscaling groups has an “instance refresh” functionality, which looks like it would fit the bill

Joe Lane 2021-03-23T12:44:33.088900Z

Does that restart the machine or replace it?

tatut 2021-03-23T13:41:17.089100Z

it creates new instances

tatut 2021-03-23T13:41:59.089300Z

tried it in our dev env that is also production topology, and it worked well

Joe Lane 2021-03-23T13:56:00.089700Z

Glad it worked for you. An important thing to remember is that i3.large / i3.xlarge instances support local valcache on the NVMe SSDs. If you replace instances with new ones, you lose a 500 / 1000 GB SSD backed cache of your database (per qg instance) and the new instances will need to rebuild that cache, one miss at a time. Maybe it's not a problem for your situation, but if you find that you're troubleshooting operational issues (degraded query performance, for example), refreshing (aka replacing) the instances shouldn't be the first thing you try. All of the above assumes your QG instances are either i3.large or i3.xlarge.


can we cancel or abort an in progress write?

Joe Lane 2021-03-23T23:07:18.090600Z

Do you mean a transaction?

Joe Lane 2021-03-23T23:08:39.090800Z

You may be looking for https://docs.datomic.com/cloud/transactions/transaction-processing.html#cancel


yes, a transaction


thank you!