On Mon, Jul 02, 2018 at 07:32:13PM +0100, Dr. David Alan Gilbert wrote:
* Fox, Kevin M (Kevin.Fox@pnnl.gov) wrote:
Can a stock kernel with all the probing still intact ever perform as well as a custom one with all the non relevant stuff stripped out? Subsecond pod starting is very handy.
I haven't benchmarked it. What is the command-line to start a second container in the existing VM? By default Kata launches a new VM.
It's an interesting question; hopefully it can get close if we: a) Configure the virtual hardware appropriately
kata-runtime already does this in the sense that only necessary devices are configured.
b) Pass kernel command line options to tell the probes to get out of the way
kata-runtime already does this. Here is the kernel command-line: tsc=reliable no_timer_check rcupdate.rcu_expedited=1 i8042.direct=1 i8042.dumbkbd=1 i8042.nopnp=1 i8042.noaux=1 noreplace-smp reboot=k console=hvc0 console=hvc1 iommu=off cryptomgr.notests net.ifnames=0 pci=lastbus=0 debug panic=1 initcall_debug nr_cpus=4 ip=::::::<blob>::off:: initcall_debug is a strange one since it can slow things down by printing lots of output to the console. I haven't measured how much difference it makes though.
c) Maybe pass firmware/ACPI data for the same type of thing. (Not investigated)
Firmware startup time can definitely be reduced. Up until now people have custom-compiled SeaBIOS to get great startup times, but similar times could be achieved with runtime detection. Stefan