Hi Tony,
On 3/7/2024 1:14 PM, Luck, Tony wrote:
Thinking about it even differently. The goal is to give information to userspace so we need to think about what would help user space? For example, what if there is a file in info that shows which CPUs are associated with each domain?
Reinette,
Interesting idea. That would save users from having to chase through /sys/devices/system/cpu/cpu*/cache/index?/* to figure out what the domain numbers in schemata files and the mon_data/mon_L3_XX values mean.
May be extra useful for ARM which seems to have big random-looking numbers for domains that came out of ACPI tables.
For SNC it would get the user directly to what they probably care about (which CPUs are in which domain).
I agree.
So something like this for an SNC 2 system:
$ cat /sys/fs/resctrl/info/L3/cpus 0: 0-35,72-107 1: 36-71,108-143
$ cat /sys/fs/resctrl/info/L3_MON/cpus 0: 0-17,72-89 1: 18-35,90-107 2: 36-53,108-125 3: 54-71,126-143
[maybe there is a better name than "cpus" for this file?]
Thank you for the example. I find that significantly easier to understand than a single number in a generic "nodes_per_l3_cache". Especially with potential confusion surrounding inconsistent "nodes" between allocation and monitoring.
How about domain_cpu_list and domain_cpu_map ?
Reinette