Moinak Ghosh wrote: > J?rgen Keil wrote: > >> Bart wrote: >> >> >> >>> The more interesting question is >>> MB/sec from the dvd drive during the install. >>> >>> >> And note that in a lot of cases the MB/sec from the optical drive >> during the install is quite low, because hsfs issues 2k read >> requests to the drive, even when reading a multi-megabyte >> compressed package archive file. AFAIK, file data on the iso9660 >> installation media doesn't use sector interleaving, so hsfs could >> do a much better job here and read ahead data in bigger clusters. >> >> Test case: watch "iostat -xnzc 5" while reading from an >> optical media, using different block sizes: >> >> dd if=/dev/rdsk/c2t1d0p0 of=/dev/null bs=2k >> dd if=/dev/rdsk/c2t1d0p0 of=/dev/null bs=32k >> >> This SONY DVD RW AW-G170A (and a DVD-RW media) >> is reading ~3 MB/sec using 2k read requests, and ~8 MB/sec >> when using 32k reads. >> >> > > My hsfs enhancements for Live Media fix this shortcoming of hsfs. > It issues whole page reads where there is no interleaving and does > re-ordering. So it can coalesce multiple pages into a single larger > read. > > I sent out the changes for review on caiman-discuss sometime back. > http://bugs.opensolaris.org/view_bug.do?bug_id=6588256 > > http://www.genunix.org/distributions/belenix_site//binfiles/hsfswebrev/index.htm >
Forgot to mention that the overall install time also depends on how fast the rest of the system is: I/O bus, disk, processor etc. On laptops with slower disk, cpu etc. the pkgadds and whole bunches of postinstall, preinstall, class-action and other scripts, bunzip2 take time so the CDROM spins down. The install in that case will be unable to sustain an 8MB/sec throughput regardless of filesystem enhancements. Regards, Moinak. > Regards, > Moinak. > > >> >> This message posted from opensolaris.org >> _______________________________________________ >> install-discuss mailing list >> install-discuss at opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/install-discuss >> >> > > _______________________________________________ > install-discuss mailing list > install-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/install-discuss >
