3 ms·

It also wraps every query in an explicit transaction unnecessarily causing locks to be held while waiting for the commit from the server which got held up behin

by Rapzid 4y ago

It also wraps every query in an explicit transaction unnecessarily causing locks to be held while waiting for the commit from the server which got held up behind some cpu intensive block in separate thread (prob some other request deserializing and hydrating those 100s of entities you mentioned). Side note: I really dislike Rails.

jemmyw 4y ago
> It also wraps every query in an explicit transaction unnecessarily causing locks to be held while waiting for the commit from the server no it doesn't. It only wraps updates in transactions, and a single line update would have an implicit transaction at the database anyway.
- Rapzid 4y ago
  It would have an implicit transaction, wouldn't it? Think about what we both wrote here (sans the weak man argument, of course I'm talking about updates).
  - jemmyw 4y ago
    I see. Well you could have been more explicit in your original message, I don't think it was obvious at all that you were talking about updates. Rails does the right thing here in my opinion. Anything that happens between calling `.save` and it returning should be in the safe envelop of a transaction. It can't know that you're only going to emit a single UPDATE query in that transaction, plus the framework user expects any exception between calling save and it returning to roll back. There are outs if you need them. I've worked on a few reasonably high traffic and complex rails applications and I don't recall a time when the time between the last query and the commit caused an issue. Yes times when the transaction itself had got too large and that commit was taking awhile. That said, there were more of these types of locking issues in the project I worked on 10 years ago with MySQL and repeatable read isolation level than with PG since then which defaults to read committed.

3 ms·

It also wraps every query in an explicit transaction unnecessarily causing locks to be held while waiting for the commit from the server which got held up behin

by Rapzid 4y ago

jemmyw 4y ago
> It also wraps every query in an explicit transaction unnecessarily causing locks to be held while waiting for the commit from the server no it doesn't. It only wraps updates in transactions, and a single line update would have an implicit transaction at the database anyway.
- Rapzid 4y ago
  It would have an implicit transaction, wouldn't it? Think about what we both wrote here (sans the weak man argument, of course I'm talking about updates).
  - jemmyw 4y ago
    I see. Well you could have been more explicit in your original message, I don't think it was obvious at all that you were talking about updates. Rails does the right thing here in my opinion. Anything that happens between calling `.save` and it returning should be in the safe envelop of a transaction. It can't know that you're only going to emit a single UPDATE query in that transaction, plus the framework user expects any exception between calling save and it returning to roll back. There are outs if you need them. I've worked on a few reasonably high traffic and complex rails applications and I don't recall a time when the time between the last query and the commit caused an issue. Yes times when the transaction itself had got too large and that commit was taking awhile. That said, there were more of these types of locking issues in the project I worked on 10 years ago with MySQL and repeatable read isolation level than with PG since then which defaults to read committed.