On Wed, Oct 14, 2020 at 06:09:13AM +0100, Leo Yan wrote:
> This patch set is to refine metrics output organization.
>
> If we reivew the current memory metrics in Perf c2c tool, it doesn't
> orgnize the metrics with directive approach; thus user needs to take
> time to dig into every statistics item. On the other hand, if use the
> "summary and breakdown" approach, the output result will be easier for
> reviewing by users, e.g. the output result can firstly give out the
> summary values, and then the later items will breakdown into more
> detailed statistics.
>
> For this reason, this patch is to reorgnize the metrics and it only
> changes for the "Shared Data Cache Line Table": it firstly displays the
> summary values for total records, total loads, total stores; then it
> breaks these summary values into small values, with the order from the
> most near memory node ("CPU Load Hit") to more far nodes
> ("LLC Load Hit", "RMT Load Hit", "Load Dram").
>
> "LLC Load Hit" = "LclHit" + "LclHitm"
>
> "RMT Load Hit" = "RmtHit" + "RmtHitm" \
> -> LLC Load Miss
> "Load Dram" = "Lcl" + "Rmt" /
>
> Another main reason for this patch set is wanting to extend "perf c2c"
> to support Arm SPE memory event, but Arm SPE doesn't contain 'HTIM' tag
> in its default trace data, for this case if want to analyze cache false
> sharing issue, we need to rely on LLC metrics + multi-threading info.
> So this patch set can be friendly to show LLC related metrics in the
> "Shared Data Cache Line Table"; for sorting cache lines with LLC metrics
> which will be sent out with another separate patch set.
>
> Before:
>
> =================================================
> Shared Data Cache Line Table
> =================================================
> #
> # ----------- Cacheline ---------- Total Tot ----- LLC Load
> Hitm ----- ---- Store Reference ---- --- Load Dram ---- LLC Total
> ----- Core Load Hit ----- -- LLC Load Hit --
> # Index Address Node PA cnt records Hitm Total Lcl
> Rmt Total L1Hit L1Miss Lcl Rmt Ld Miss Loads
> FB L1 L2 Llc Rmt
> # ..... .................. .... ...... ....... ....... ....... .......
> ....... ....... ....... ....... ........ ........ ....... .......
> ....... ....... ....... ........ ........
> #
> 0 0x55acdcc92100 0 8197 40716 52.18% 3170 3170
> 0 24466 24437 29 0 0 0 16250
> 3349 5909 0 3822 0
> 1 0x55acdcc920c0 0 1 4621 31.01% 1884 1884
> 0 0 0 0 0 0 0 4621
> 739 0 0 1998 0
> 2 0x55acdcc92080 0 1 4475 16.69% 1014 1014
> 0 0 0 0 0 0 0 4475
> 2405 0 0 1056 0
>
>
> After:
>
> =================================================
> Shared Data Cache Line Table
> =================================================
> #
> # ----------- Cacheline ---------- Tot ------- Load Hitm -------
> Total Total Total ---- Stores ---- ----- Core Load Hit ----- -
> LLC Load Hit -- - RMT Load Hit -- --- Load Dram ----
> # Index Address Node PA cnt Hitm Total LclHitm RmtHitm
> records Loads Stores L1Hit L1Miss FB L1 L2
> LclHit LclHitm RmtHit RmtHitm Lcl Rmt
> # ..... .................. .... ...... ....... ....... ....... .......
> ....... ....... ....... ....... ....... ....... ....... .......
> ........ ....... ........ ....... ........ ........
> #
> 0 0x55acdcc92100 0 8197 52.18% 3170 3170 0
> 40716 16250 24466 24437 29 3349 5909 0
> 3822 3170 0 0 0 0
> 1 0x55acdcc920c0 0 1 31.01% 1884 1884 0
> 4621 4621 0 0 0 739 0 0
> 1998 1884 0 0 0 0
> 2 0x55acdcc92080 0 1 16.69% 1014 1014 0
> 4475 4475 0 0 0 2405 0 0
> 1056 1014 0 0 0 0
I haven't used the tool for some time, so it's fine with me,
but there might be some people already used to see certain
columns in place and I don't want to make them angry unless
there's really good reason for that ;-)
Joe, could you please check on these changes?
thanks,
jirka
>
>
> Leo Yan (8):
> perf c2c: Display the total numbers continuously
> perf c2c: Display "Total Stores" as a standalone metrics
> perf c2c: Organize metrics based on memory hierarchy
> perf c2c: Change header from "LLC Load Hitm" to "Load Hitm"
> perf c2c: Use more explicit headers for HITM
> perf c2c: Change header for LLC local hit
> perf c2c: Correct LLC load hit metrics
> perf c2c: Add metrics "RMT Load Hit"
>
> tools/perf/builtin-c2c.c | 83 +++++++++-------------------------------
> 1 file changed, 18 insertions(+), 65 deletions(-)
>
> --
> 2.17.1
>
