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Hi Fabio, At the moment my main priority has been to verify that I've understood the metrics I'm collecting correctly. When I compare some of the metrics to data I'm getting from node_exporter there are still some questions, so I'm doing some digging trying to make sure I've understood what is being reported through monitoring. I'm currently developing another python tool to use inotify to parse .cinfo files on modification, I'm planning to use this data to track the use of a the cache in order to try and optimise performance. I've got a very basic Pfc decisionlib working right now similar to osschar/xrdpfc-decision-ucsd on github, but I've not tested it against production workloads, the plan is to publish code once we have something tested that doesn't at least make performance worse. Best Regards, Rob On 2022-04-15 19:58, Fabio Andrijauskas wrote: > This email was sent to you by someone outside the University. > You should only click on links or attachments if you are certain that > the email is genuine and the content is safe. > > Hi all, > > The problem was timing, now the script deletes the file from the cache > and my monitoring system is able to request the file. Using the > G-stream from the cache I can check other details about these tests. > > @Robbert, this is very interesting! Are these hacks on GitHub or > similar? > > -- > Fábio Andrijauskas > > On Wed, Apr 13, 2022 at 3:32 AM CURRIE Robert <[log in to unmask]> > wrote: > >> Hi, >> >> I had understood that the point of the XrdPfcCommand was to allow for >> a certain file to be removed from the cache with a call to the service >> for testing. >> https://github.com/xrootd/xrootd/blob/6b0209fd262f9f571e93daef17df1724dac8eed5/src/XrdPfc/XrdPfcCommand.cc#L268 >> >> I don't know if this is this still supported as I haven't tested it >> (yet). I've just removed the files from disk and haven't had the >> server react badly from me doing so, it just looks for the file, finds >> it missing and re-acquires it. >> >> @Fabio Andrijauskas I've been looking into modifying/expanding the Pfc >> recently at Edinburgh. >> (nothing other than ugly local hacks on a test instance for now). >> I think we're mainly interested from a cache performance improvement >> angle, and possibly building a set of cache/purge decision libraries >> which we can configure, but I've also been looking at the monitoring >> data with some interest to compare it to our .cinfo file monitor. >> >> Best Regards, >> >> Rob >> >> ------------------------- >> >> From: [log in to unmask] <[log in to unmask]> on >> behalf of Andrew Hanushevsky >> <[log in to unmask]> >> Sent: 13 April 2022 01:08 >> To: Fabio Andrijauskas <[log in to unmask]> >> Cc: [log in to unmask] <[log in to unmask]> >> Subject: Re: Delete a file from rooted cache >> >> This email was sent to you by someone outside the University. >> You should only click on links or attachments if you are certain that >> the email is genuine and the content is safe. >> >> Hi Fabio, >> >> There is no way to flush (effectively delete) a file from the cache. >> We >> have talked about providing such a feature but didn't have a use case >> for >> it. Anyway, I assume you are logging into the Xcache server and >> physically >> removing the files. As long as you do that when no one is using the >> file a >> subsequent xrdcp should not hang. So, I suspect the timing was a bit >> off >> or I don't understand the actual steps you were taking. >> >> Andy >> >> On Tue, 12 Apr 2022, Fabio Andrijauskas wrote: >> >>> Hi Folks, >>> >>> I am improving the Xrootd cache monitoring on OSG, and I would like >>> to >>> check if the cache can provide a cached file and if the cache can >>> fetch a >>> file from the origin. To check the origin cache process, I want to >>> delete a >>> specific file on the cache and request this file on the client, in >>> that way >>> forcing the cache to fetch the origin file. >>> >>> I am deleting 4 files, two links, and two files related to this >>> cached file. However, when I do that, the xrdcopy process hangs and >>> timeout. So, I need to restart the cache to back to the regular >>> operation. >>> >>> What is the right way to force the cache to fetch a file on the >>> origin? >>> >>> >>> >>> *--Fábio Andrijauskas* >>> >>> ######################################################################## >>> Use REPLY-ALL to reply to list >>> >>> To unsubscribe from the XROOTD-L list, click the following link: >>> https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=XROOTD-L&A=1 [1] >>> >> >> ######################################################################## >> Use REPLY-ALL to reply to list >> >> To unsubscribe from the XROOTD-L list, click the following link: >> https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=XROOTD-L&A=1 The >> University of Edinburgh is a charitable body, registered in Scotland, >> with registration number SC005336. Is e buidheann carthannais a th' >> ann an Oilthigh Dhùn Èideann, clàraichte an Alba, àireamh clàraidh >> SC005336. 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