Use hiredis

[Andrew-Chen-Wang]

Description

Using hiredis, which is developed by the redis community, too, is probably best performance wise.

Benchmarks (came when I was using aioredis for websocket pubsub): https://github.com/popravich/python-redis-benchmark

Rationale

Since Redis is already used in this project, why not use hiredis? Windows is not supported by Redis and Hiredis; however, Redis could be supported via Docker.

Another thing is most production-ready Django projects don't use Windows servers. So I've put hiredis as a mandatory thing in production (since celery uses redis in local, too, so separate occasions for the hiredis requirements).

Use case(s) / visualization(s)

More performant redis

[jcass77]

I was always under the impression that redis-py would revert to using the HiredisParser automatically if it was available?

Are there some specific implementation details in the Django cache that requires this to be done explicitly? (I haven't checked).

[Andrew-Chen-Wang]

redis-py would, but I don't think Django-redis does. I've never tested it, but I couldn't find an issue saying Django-redis was default using it.

Edit: I did test it, but it was so varying in my own tests (using debug toolbar), that there wasn't much of a noticeable difference.

[jcass77]

Looks like django-redis leaves this up to redis-py: https://github.com/jazzband/django-redis/blob/dceb86fb0a25edbd966a27f797121e3dd60674b6/django_redis/pool.py#L82-L86

...and DefaultParser reverts to HiRedis if available: https://github.com/andymccurdy/redis-py/blob/09da3ad07f26350d093929fe1ea6eaaca79ab944/redis/connection.py#L485-L488

[browniebroke]

I'm OK to add this. Noted a few edge cases with Docker + Windows.

[wadkar]

I am a bit confused here. The line tells me that if people are not using docker and they have said yes to windows, we force the use of hiredis in production? Is this intentional?

[Andrew-Chen-Wang]

Yes, it's just wrong to use a Windows machine to deploy a server. If you take a look at base.txt, it has a different condition for if you use Windows or Docker. If you do use Windows but not docker, you cannot build hiredis. But, since you wanted to use Redis, you'll also get hiredis for production, assuming, with hope, that you deploy with a unix.

However, if you use Docker on Windows, you should be able to build hiredis, and thus it can go into base.txt.

[wadkar]

Ah, thanks - that clarifies a lot. I see this is mentioned in the description as well but it didn't click until now.

Thanks a lot!

[browniebroke]

Thanks 🎉