On Fri, Apr 01, 2016 at 07:41:31PM +0100, Richard W.M. Jones wrote: > Below are some benchmarks of the other things you mentioned. These > are complete appliance boot-to-shutdown times [*not* just SeaBIOS]. > All debugging has been disabled, and I'm using a slightly different > kernel version, so these runs are not comparable to earlier results I > posted. All times are the mean of 10 runs. The ± number is 1 > standard deviation from the mean. > > In my estimation only CONFIG_FW_ROMFILE_LOAD=n seems to make a > measurable difference. > > ---------------------------------------------------------------------- > Ordinary qemu SeaBIOS configuration > Result: 1227.5ms ±7.7ms > > -bios boot-fast.bin, as per my previous patch > Result: 1113.7ms ±6.4ms > > Leaving CONFIG_XEN and CONFIG_THREADS at default settings > Result: 1111.2ms ±3.8ms > > CONFIG_USE_SMM=n > Result: 1116.0ms ±5.0ms > > CONFIG_FW_ROMFILE_LOAD=n > Result: 1106.6ms ±5.0ms > > CONFIG_RELOCATE_INIT=n > Result: 1104.7ms ±11.2ms > ----------------------------------------------------------------------
Actually, CONFIG_RELOCATE_INIT=n looks like it is doing something, but the error bars are quite large. Here's another one that makes a difference: CONFIG_BOOTORDER=n Result: 1099.5ms ±3.7ms (Since we're using -kernel, we don't care about bootorder) Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://people.redhat.com/~rjones/virt-df/