Added "defaultMemoryMbytes" to actor.json

[jancurn]

see https://apify.slack.com/archives/C010Q0FBYG3/p1733154485910689

[fnesveda]

Are we sure we want to have it this customizable? Right now the memory has to be a power of 2, which would be hard to enforce with a custom expression. We could relax the "power of 2" requirement, but I'm a bit worried about the implications on job allocation to workers if we allow completely custom memory.

Also it might be more readable to put defaultMemoryMbytes between minMemoryMbytes and maxMemoryMbytes, to make it a bit more clear that the calculated value is clamped from both sides, and have one comment for all three together.

[jancurn]

Right now the memory has to be a power of 2,

We could say we always ceil it to the next higher value available by the platform. This should apply to all three parameters.

Are we sure we want to have it this customizable?

I think it's better to use an expression rather than some A and B linear coefficients.

[metalwarrior665]

I like this. This would probably remove the need to have charge the actor-start per GB or maybe charge it at all. No, this is just a default, they could override it so we would still have to charge per GB for the wrong configurers

[jancurn]

I like this. This would probably remove the need to have charge the actor-start per GB or maybe charge it at all. No, this is just a default, they could override it so we would still have to charge per GB for the wrong configurers

In theory in the future we might disable ability to select custom memory, or per developer setting. This opens the path.

[jancurn]

BTW perhaps this would be cleaner:

memory: {
  minMbytes: 128,
  maxMbytes: 4096,
  defaultMbytes: "${maxCrawlPages} * 256 + 128"
  // default: 1024 - this also works
}

What do you think guys?

[fnesveda]

How about this?

• move mbytes suffix one higher
  • it's cleaner, but if there would be some other memory config which isn't directly related to the mbytes of memory available, it can't go into the object
• prefix the variables with input. to make it clear that they're referring to input values, not other values from actor.json

memoryMbytes: {
    min: 128,
    default: "${input.maxCrawlPages} * 256 + 128"
    max: 4096,
}

[jancurn]

IMO it's better to keep just memory, to have flexibility to add more stuff in the future. Also the convention is that variable names must end with the unit, not parent objects. So:

memory: {
    minMbytes: 128,
    defaultMbytes: "${input.maxCrawlPages} * 256 + 128"
    maxMbytes: 4096,
}

[jancurn]

Or maybe we could make it even more generic and future proof:

runtime: {
    memoryMinMbytes: 128,
    memoryDefaultMbytes: "${input.maxCrawlPages} * 256 + 128"
    memoryMaxMbytes: 4096,
}

Plus I agree with ${input.maxCrawlPages}, it just needs to be consistent syntax with OUTPUT_SCHEMA.json