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On 11/06/2015 12:19 PM, Michał Górny wrote: |
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> On Fri, 6 Nov 2015 11:49:44 -0800 |
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> Zac Medico <zmedico@g.o> wrote: |
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> |
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>> On 11/06/2015 11:34 AM, Michał Górny wrote: |
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>>> On Fri, 6 Nov 2015 10:58:23 -0800 |
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>>> Zac Medico <zmedico@g.o> wrote: |
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>>> |
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>>>> On 11/06/2015 10:39 AM, Michał Górny wrote: |
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>>>>> On Fri, 6 Nov 2015 09:24:15 -0800 |
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>>>>> Zac Medico <zmedico@g.o> wrote: |
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>>>>> |
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>>>>>> On 11/06/2015 12:20 AM, Alexander Berntsen wrote: |
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>>>>>>> On 06/11/15 09:05, Michał Górny wrote: |
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>>>>>>>>>> I know nothing about the egencache stuff. Maybe Michał can |
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>>>>>>>>>> comment? |
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>>>>>>>> Michał finds this black magic. Trusts zmedico. |
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>>>>>>> I think it looks like it's probably supposed to be reasonable, perhaps. |
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>>>>>>> |
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>>>>>>> Maybe Brian can look at it. At least that way we'll have a lot of |
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>>>>>>> people that attempted understanding what's going on. |
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>>>>>>> |
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>>>>>>> Maybe we need a "Trusted-by:" line. |
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>>>>>>> |
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>>>>>> |
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>>>>>> Maybe it helps if I give some more context. At my workplace, we have |
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>>>>>> lots of scripts that call `emerge --sync private-work-repo` to ensure |
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>>>>>> that the current system has the latest changes from private-work-repo. |
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>>>>>> It can be annoying if it spends the bulk of its time calling hooks, even |
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>>>>>> though private-work-repo was already up-to-date: |
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>>>>>> |
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>>>>>>>>> Timestamps on the server and in the local repository are the same. |
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>>>>>>>>> Cancelling all further sync action. You are already up to date. |
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>>>>>> |
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>>>>>> So, we want to skip the hooks when repos are already up-to-date. In this |
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>>>>>> case, there's no point in calling hooks or updating the metadata cache. |
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>>>>> |
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>>>>> This is incorrect assumption. A change in master repo may trigger |
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>>>>> metadata cache update in slaved repo. |
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>>>>> |
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>>>> |
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>>>> Good point. I'll update it to account for this. |
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>>> |
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>>> Please don't. This is just one of the corner cases when it will fail. |
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>>> You can't assume any post-sync hook can be skipped if X or Y didn't |
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>>> change. |
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>> |
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>> Can you give an example use case? It the sync operation did not change |
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>> anything, then how is it useful to run hooks? |
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> |
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> I've already given you one example. I'm afraid there may be more |
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> customized scripts where not being run is at least unexpected. The gain |
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> is minor compared to the potential damage and confusion. |
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> |
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|
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Yeah, I guess some people might be working under the assumption that |
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emerge --sync will *always* call their hook, in order to trigger some |
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system administration tasks that have little or nothing to do with the |
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sync operation itself. It's impossible to speculate how many people |
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might be relying on this sort of behavior. |
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|
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So, I'll think about exposing an environment variable to the hooks which |
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will allow them to decide if anything relevant has changed. |
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-- |
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Thanks, |
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Zac |
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