How scalable is Parse?
I've been considering using Parse.com's service for my backend, but I'm skeptical about its scalability.
Can it really handle several thousand simultaneous users? If not, is their any good way transitioning away from it?
Answer
I know the question may be old, but wanted to provide my 2 cents for others out there who may be considering parse....
Under the simplest of scenarios, parse may work well. As soon as you need to scale up to more complex queries, I have personally found nothing but headaches.
Queries are limited to 1000 records. Initially, you may think this is not an issue, until you start dealing with sub queries, and realize weird data is returned because the sub query cuts records off without warning or error. (FYI, the default is 100 records unless you specify a limit up to 1000, so the problem is even worse if you are not paying attention).
For some strange reason there is a limit to the number of times you can issue a count query in a min. (and this limit appears to be really low). Be prepared to try and throttle your code so you don't hit this limit, otherwise errors are thrown.
Background Jobs do not run reliably. I have had a background job set to run every 5 min, and there are times it takes 20+ min before the job will kick in.
Lots of Timeouts. This is the one that gives me the most heartburn. A. If you have a cloud function that takes a while to process, you have about 6 or 7 seconds to get it done or it will cut you off.
B. I get the feeling that there is a general instability with the system. Periodically, I run into issues which seems to last for about an hour or so where timeouts happen more frequently (and with relatively simple functions that should return immediately).
I fully regret my decision to use parse, and I am doing all I can to keep the app alive long enough for us to get funding, so we can move off the platform. If anyone has any better alternatives to parse, I am all ears.