How can i disable haswell cache prefetcher?

[zhaoguo_w_]

I try to disable haswell cache prefetcher, but there is no options in the BIOS. I also try to use wrmsr command to set 0x1a0 register the bit 9 to be 1 to disable the cache prefetcher, but failed.

# rdmsr 0x1a0

850089

#wrmsr -p 0 0x1a0 0x850289

wrmsr: CPU 0 cannot set MSR 0x000001a0 to 0x0000000000850289

[Bernard]

Do you use Linux or Windows

Sometimes write/read operations on MSR registers are locked.I had similar issue with access to MSR 0x199.

[Alexander_Alexeev]

What flags (bits number) are you trying to change in MSR? 

[Bernard]

I was using windbg to modify MSR registers.