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Unfortunately the majority of people who use asyncio in the real world do not have a need for concurrenct programming. They are drawn to it because they believ

Unfortunately the majority of people who use asyncio in the real world do not have a need for concurrenct programming. They are drawn to it because they believe it is faster, which, generally, it is not. That isn't to say there aren't reasonable usecases - but most people using asyncio are writing webapps which spend a lot of time in the CPU generating or outputting JSON/GraphQL/HTML.

nine_k 4y ago
I think this may be influenced by Node. With JS and Node, async is cheap and ergonomic, so it's very widely used, even if the latency gains are marginal. With Python and asyncio, neither assumption holds, but the idea of shaving off some latency persists: if we rewrite everything using asyncio, our DB accesses can be parallelized, yay! This may or may not be a net win in latency; reworking your DB access patterns may gain you more.
- kissgyorgy 4y ago
  > reworking your DB access patterns may gain you more. Nope: https://techspot.zzzeek.org/2015/02/15/asynchronous-python-and-databases/ https://techspot.zzzeek.org/2015/02/15/asynchronous-python-a...
  - deleted 4y ago
    [deleted]
  - nine_k 4y ago
    I don't say that asyncio gives you nothing! Go for it with your DB access if you have already gone async in your design. But often the lower-hanging fruit is doing more joins in the DB, fetching fewer columns, and writing your query more thoughtfully. Async only helps if you can do something while waiting for the DB to complete your query. A common anti-pattern, exacerbated by ORMs, is doing a bunch of small queries while passing bits of data between them in Python; moving that to asyncio won't help much, if any.
    - calpaterson 4y ago
      > But often the lower-hanging fruit is doing more joins in the DB, fetching fewer columns, and writing your query more thoughtfully. Reluctant to add a "me-too" comment but I think you have it there. For whatever reason people are much keener to investigate different ways of scheduling IO than they are to investigate what the query plan looks like and why.
  - _bohm 4y ago
    It may not be the norm, but there are definitely apps/services out there that require heavy-duty database queries and can have their throughput bottlenecked by synchronous DB IO latency, and would benefit from asyncio on the database side. Also, SQLAlchemy supports asyncio now.

nine_k 4y ago

I think this may be influenced by Node. With JS and Node, async is cheap and ergonomic, so it's very widely used, even if the latency gains are marginal. With Python and asyncio, neither assumption holds, but the idea of shaving off some latency persists: if we rewrite everything using asyncio, our DB accesses can be parallelized, yay! This may or may not be a net win in latency; reworking your DB access patterns may gain you more.

kissgyorgy 4y ago
> reworking your DB access patterns may gain you more. Nope: https://techspot.zzzeek.org/2015/02/15/asynchronous-python-and-databases/ https://techspot.zzzeek.org/2015/02/15/asynchronous-python-a...
- deleted 4y ago
  [deleted]
- nine_k 4y ago
  I don't say that asyncio gives you nothing! Go for it with your DB access if you have already gone async in your design. But often the lower-hanging fruit is doing more joins in the DB, fetching fewer columns, and writing your query more thoughtfully. Async only helps if you can do something while waiting for the DB to complete your query. A common anti-pattern, exacerbated by ORMs, is doing a bunch of small queries while passing bits of data between them in Python; moving that to asyncio won't help much, if any.
  - calpaterson 4y ago
    > But often the lower-hanging fruit is doing more joins in the DB, fetching fewer columns, and writing your query more thoughtfully. Reluctant to add a "me-too" comment but I think you have it there. For whatever reason people are much keener to investigate different ways of scheduling IO than they are to investigate what the query plan looks like and why.
- _bohm 4y ago
  It may not be the norm, but there are definitely apps/services out there that require heavy-duty database queries and can have their throughput bottlenecked by synchronous DB IO latency, and would benefit from asyncio on the database side. Also, SQLAlchemy supports asyncio now.