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doc: --max-old-space-size should be documented #32252
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+1 ... Let's just make sure that v8 flags that are documented are separated off in their own section of cli.md with clear indication in the docs that they fall outside Node.js' responsibility and therefore cannot be covered by the semver rules. Beyond that, I'm very much +1 on documenting useful v8 options.
Obviously, we should get @nodejs/v8 folks to review those first tho ;-)
If this is a good first issue, I would like to work on it. :)
Reacted by Gireesh Punathil, Alex Yang and Jacky HuWill make a PR and submit.
Reacted by Gireesh Punathil and Alex Yang- added 2 commits that reference this issue
on Mar 14, 2020 - added a commit that references this issue
on Apr 13, 2020 - added a commit that references this issue
on Apr 14, 2020 - added a commit that references this issue
on Apr 22, 2020 I'm not sure this is the right place to go, but is there any documentation of the maximum size of
max-old-space-size(or the max heap size V8 will allow)?On a machine with 256GB of ram another with 768GB of ram with a
max-old-space-sizeof 200gb and 500gb withv14.15.1, I'm not seeing a heap larger than about 16GB regardless ofmax-old-space-size. Callingv8.getHeapStatistics()shows aheap_size_limitthat matches my givenmax-old-space-sizebuttotal_heap_sizenever goes above above 16GB. I've tried withoptimize-for-sizeand without.I'm now finding that an older version that I had been using,
v10.16.0, appears to use at least 32GB... still experimenting... but if there's a doc somewhere that specifies the actual max heap allowed (maybe by version?) I would definitely read it! TIA![edit]: well it looks like
v10.16.0crashes at about 33GB with a 500GBmax-old-space-size...I'm not sure this is the right place to go, but is there any documentation of the maximum size of
max-old-space-size(or the max heap size V8 will allow)?On a machine with 256GB of ram another with 768GB of ram with a
max-old-space-sizeof 200gb and 500gb withv14.15.1, I'm not seeing a heap larger than about 16GB regardless ofmax-old-space-size. Callingv8.getHeapStatistics()shows aheap_size_limitthat matches my givenmax-old-space-sizebuttotal_heap_sizenever goes above above 16GB. I've tried withoptimize-for-sizeand without.I'm now finding that an older version that I had been using,
v10.16.0, appears to use at least 32GB... still experimenting... but if there's a doc somewhere that specifies the actual max heap allowed (maybe by version?) I would definitely read it! TIA![edit]: well it looks like
v10.16.0crashes at about 33GB with a 500GBmax-old-space-size...I am also facing this issue, I want to build a very large object, and I have 256GB physical memory. But always failed, even I set max-old-space-size already. I am using v12.18.0
- added a commit that references this issue
on Jul 27, 2026
Even though
--max-old-space-sizeis a V8 flag, I would expect us to document it, given that it’s probably the most useful V8 flag for Node.js users overall.Refs: #32251