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classification
Title: Stored (uncompressed) ZipExtFile in zipfile can be seekable at lower cost
Type: enhancement Stage: patch review
Components: Library (Lib) Versions: Python 3.11
process
Status: open Resolution:
Dependencies: Superseder:
Assigned To: gregory.p.smith Nosy List: alanmcintyre, gregory.p.smith, juniorjpdj, serhiy.storchaka, twouters
Priority: normal Keywords: patch

Created on 2021-05-19 02:28 by juniorjpdj, last changed 2022-04-11 14:59 by admin.

Pull Requests
URL Status Linked Edit
PR 26227 closed juniorjpdj, 2021-05-19 02:30
PR 27737 open juniorjpdj, 2021-08-12 04:24
Messages (1)
msg393918 - (view) Author: JuniorJPDJ (juniorjpdj) * Date: 2021-05-19 02:28 
At the moment stored ZipExtFile is being read to the place of seek like all other compressed variants.
It's not needed as it's possible to freely seek uncompressed file inside zip without this penalty.

Lots of apps depend on ZipExtFile seeking ability and it would lower performance and IO penalty significantly.

I've POC patch created.
It disables CRC checking after first seek as it's impossible to check CRC if we are not reading whole file.
History
Date User Action Args
2022-04-11 14:59:45adminsetgithub: 88339
2021-08-18 17:30:30gregory.p.smithsetassignee: gregory.p.smith

nosy: + gregory.p.smith
2021-08-12 04:24:16juniorjpdjsetpull_requests: + pull_request26217
2021-08-12 03:44:40terry.reedysetnosy: + twouters, alanmcintyre, serhiy.storchaka
2021-05-19 02:30:41juniorjpdjsetkeywords: + patch
stage: patch review
pull_requests: + pull_request24844
2021-05-19 02:28:39juniorjpdjcreate