snoopy@sopwith.UUCP (Snoopy) (06/04/89)
In article <400@amc-gw.UUCP> jhall@emu.UUCP (John Hall) writes: | I would be willing to take a performance hit in namei(), if this idea | was well implemented. Think of the incredible functionality it would | provide! In any case, namei() is used only when opening "files" and | slightly lower performance here would not affect system performance | much at all. "With the addition of the two caches, the percentage of system time devoted to name translation dropped from 25 percent to less than 10 percent." _The Design and Implementation of the 4.3BSD UNIX Operating System_ by Leffler, McKusick, Karels, and Quarterman It appears that namei() soaks up more cycles than one might expect. _____ .-----. /_____\ Snoopy ./ RIP \. /_______\ qiclab!sopwith!snoopy | | |___| parsely!sopwith!snoopy | tekecs | |___| sun!nosun!illian!sopwith!snoopy |_________| "I *am* the next man!" -Indy
libes@cme.nbs.gov (Don Libes) (06/05/89)
In article <201@sopwith.UUCP> snoopy@sopwith.UUCP (Snoopy) writes: >"With the addition of the two caches, the percentage of system time >devoted to name translation dropped from 25 percent to less than 10 >percent." > > _The Design and Implementation of the 4.3BSD UNIX Operating System_ > by Leffler, McKusick, Karels, and Quarterman > >It appears that namei() soaks up more cycles than one might expect. You misunderstood the quote. It doesn't say anything about percentage of *total* system time. Don Libes libes@cme.nbs.gov ...!uunet!cme-durer!libes
snoopy@sopwith.UUCP (Snoopy) (06/07/89)
In article <1245@muffin.cme.nbs.gov> libes@cme.nbs.gov (Don Libes) writes: |In article <201@sopwith.UUCP> snoopy@sopwith.UUCP (Snoopy) writes: |>"With the addition of the two caches, the percentage of system time |>devoted to name translation dropped from 25 percent to less than 10 |>percent." |> |> _The Design and Implementation of the 4.3BSD UNIX Operating System_ |> by Leffler, McKusick, Karels, and Quarterman |> |>It appears that namei() soaks up more cycles than one might expect. | |You misunderstood the quote. It doesn't say anything about percentage |of *total* system time. From the beginning of section 7.8: "Profiling studies show that nearly one-quarter of the time in the kernel is spent in the pathname-translation routine, namei(), translating pathnames to inodes." Then they tell what namei() does, and how they added caches to make it faster, and finally give the results quoted above (25% -> 10%). If I misunderstood, I still do. If they aren't refering to the total system time, what *are* they refering to? _____ .-----. /_____\ Snoopy ./ RIP \. /_______\ qiclab!sopwith!snoopy | | |___| parsely!sopwith!snoopy | tekecs | |___| sun!nosun!illian!sopwith!snoopy |_________| "I *was* the next man!" -Indy