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Hi, Thanks for this Andy, it's very helpful. I'm confused why 'Read' is *always* zero on our cache log stats, I would have expected it to be a multiple of the pagesize. Have I got the wrong end of the stick here? Cheers Tom > -----Original Message----- > From: [log in to unmask] <[log in to unmask]> On > Behalf Of Andrew Hanushevsky > Sent: 02 March 2020 23:59 > To: Patargias, George (STFC,RAL,SC) <[log in to unmask]> > Cc: [log in to unmask] > Subject: Re: Meaning of memory cacheing log stats > > Hi George, > > So, here it is: > > 0 Read; Total number of bytes read into the cache > 38581 Get; Number of bytes delivered from the cache > 0 Pass; Number of bytes read but not cached > 0 Write; Total number of bytes written from the cache > 0 Put; Number of bytes updated in the cache > 20 Hits; Number of times wanted data was in the cache > 3 Miss; Number of times wanted data was *not* in the cache > 0 pead; Bytes read via preread (not included in BytesRead) > 0 HitsPR; Number of pages of wanted data was just preread > 0 MissPR Number of pages of unwanted data was just preread > > So, it would seem the cache is being effective as number of hits is far greater > than the number of misses. > > Andy > > > On Mon, 2 Mar 2020, George Patargias - UKRI STFC wrote: > > > Hello, > > > > > > We have turned on the printing of mem cache statistics using the > > "logstasts" flag of the pss.cache > > > > directive as shown below > > > > > > pss.cache logstats max2cache 33554432 pagesize 33554432 size > > 17179869184 > > > > > > Can you please explain briefly what is the meaning of the numbers > appearing in the corresponding lines of the xrootd log? The following is a > common example we see on our xrootd server but it is not clear whether the > cache is being effective in this case (we suspect it isn't). > > > > > > Cache: Stats: 0 Read; 38581 Get; 0 Pass; 0 Write; 0 Put; 20 Hits; 3 > Miss; 0 pead; 0 HitsPR; 0 MissPR; Path > > > > > > Thanks, > > > > > > George > > > > > ############################################################ > ########## > > ## > > 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 > > > > ############################################################ > ############ > 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 ######################################################################## 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