I have not used Cascalog, so I do not know how much variation from one run to the next is completely normal, but there are many factors that can cause variations in run time between runs in most computations. For example:
+ the state of L1, L2, etc. caches in the CPU memory systems + If files are being accessed on a mechanical disk, where they are, where the disk is, where the read/write head is, and which disk blocks are currently cached in the operating system's memory + If multiple nodes are involved, what other traffic is on the network + What other processes are running, and how much time they take away from your process, and how they affect the state of all of the other things above. + For JVM processes, as Clojure/Java is, whether or not the JIT compiler runs on your code, and if so, how the execution that occurred so far up to that point affects its "choices" in what kind of optimized code to produce. I'm probably forgetting half a dozen other factors. I consider it somewhat unusual to see results that vary less than 5% from run to run. Andy On Wed, Jun 11, 2014 at 5:58 AM, sindhu hosamane <sindh...@gmail.com> wrote: > I have set up a single node hadoop and running my cascalog queries on it > . > Good and i get results too . Now i am using clojure.core/time to > evaluate how much time cascalog queries took for execution. > Very Strange thing is: each time i run the cascalog query , i get > different elapsed time for same query . > For example (what i tried) : > > (time > > > > > > > *(?<- (stdout) [?timestamp ?assembly ?category ] (info-tap > :> ?timestamp ?assembly ?category ) (clojure.string/trim ?category :> > ?trimmed-category) (= ?trimmed-category "Start Inhibit")) )when i run > 1st time : Elapsed time: 610.221708 msecswhen i run 2nd time : Elapsed > time :787.81836 msecswhen i run 3rd time : Elapsed time : 680.919887 > msecsPlease let me know whats wrong ?. I Need to make Performance tests on > cascalog queries , this should be accurate .Hoping to get help from someone > .Thank you ,- Sindhu.* > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with > your first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en > --- > You received this message because you are subscribed to the Google Groups > "Clojure" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to clojure+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
