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On 02/27/2016 11:50 PM, Robin H. Johnson wrote: |
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> On Sat, Feb 27, 2016 at 02:14:12PM +0100, Luca Barbato wrote: |
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>> On 24/02/16 01:33, Duncan wrote: |
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>>> That option is there, and indeed, a patch providing it was specifically |
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>>> added to portage for infra to use, because appending entries to existing |
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>>> files is vastly easier and more performant than trying to prepend entries |
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>>> and having to rewrite the entire file as a result. |
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>> This sounds wrong in many different ways. The changelog files are tiny |
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>> and makes next to no difference truncate+write or append. |
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> Prior to seperating ChangeLog files into years, this was way worse: |
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> a kernel bump present in any of gentoo-sources, hardened-sources, |
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> vanilla-sources meant another 100k of data to sent. It's not a lot |
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> overall, but here's some quick stats from one of our rsync servers, on |
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> bytes sent. |
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[snip] |
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> |
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> So, now the question: |
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> If we use appending changelogs, the large changelogs only differ by a |
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> few hundred bytes. If we instead have to rewrite them, it's 50k+ per |
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> changelog. |
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from /usr/share/portage/config/make.globals: |
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PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times |
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--omit-dir-times --compress --force --whole-file --delete --stats |
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--human-readable --timeout=180 --exclude=/distfiles --exclude=/local |
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--exclude=/packages --exclude=/.git" |
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Notice the --whole-file part there. |
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> |
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> For each 50k changelog, the median transfer would get 0.25% larger. |
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> |
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Well, we could just have less changes ;) |
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160GB/day per server is about 2MB/s, ~16Mbit, or about 5TB/month. That's |
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still included in the 'free' bandwidth that el cheapo hosters like |
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Hetzner provide with their smallest servers ... |
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