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Define chunk size for `ReadableStream` created by `blob::stream()`

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#144 12 comments 1 reaction 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
30/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
html, wasm
Domain
api, documentation

Research direction

Start with this issue and compare the File API and Streams specification sections referenced in the discussion. Determine which specification owns the ReadableStream chunk-size behavior and whether a fixed 0x10000 value can be specified; done means the responsible specification and normative requirement are agreed and documented.

Written by the indexing model from the issue text.

Description

Currently regarded as 'Issue 1' I have recently come across a project that forces me to assume the chunk size for the stream. Testing with chromium and firefox, the chunk size appears to be 0x10000 or 65536. I cannot find a reason why it's this particular number.

As I'm making a wasm module, I must allocate memory space when going through files 5GB+ in size. I will allocate 0x10000 bytes for now, but only out of assumption... if there's a browser out there that does not follow this assumption then there will be fatal bugs.

I'm not sure if this is w3c/FileAPI/'s or streams.spec.whatwg.org's jurisdiction. But neither of them has an exact number.

Dominant language
HTML
Stars
118
Forks
52
Avg merge
9d 16h
Merged PRs (30d)
1

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