Roland Mainz wrote: > Casper.Dik at Sun.COM wrote: > >>> 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. >>> >> While this matters some, the current install process is so inefficient >> that even though installing from DVD is slower than the network, a network >> tends to be idle most of the time during the install. >> >> (Which isn't surprising as getting 4GB over local net should not take more >> than between 40 (Gbps) and 400s (100Mbps) but installs take generally a lot >> longer than 7 minutes; bunzip2 is also so slow that it cannot stream data >> from any media faster than papertape. >> > > "bunzip" could be made a bit faster with some simple tricks (like using > higher optimizer options for the compiler, use largepages for the > buffers etc.) ... but it would need a sponsor for such a patch > (<rant>which is unlikely to happen since I am already sitting on at > least half a dozend bugs/RFEs awaiting sponsorship and noone cares... > ;-( </rant>) ... >
Or replace bzip2 with 7zip which has 15% higher compression and faster decompression speed as compared to bzip2. The unix implementation (p7zip) is probably LGPL. Regards, Moinak. > ---- > > Bye, > Roland > >
