How to use "ipmwatch" with PMEM200 and 3rd Gen Xeon?

[csfrogy]

Hi, I just read from some papers that "ipmwatch" utility can be used to measure the read/write to Optane DCPMM. 

My device uses PMEM200 (2nd Gen Optane DCPMM) and 3rd Gen Xeon processor (Xeon Gold 6348 CPU).

When I download and install ipmwatch with YUM and use it, the message shows that "Intel Optane DIMMS are not available on this system."

When I download and install ipmwatch with code in intel/intel-pmwatch (github.com)   , the message shows that "Unsupported firmware."

Does "ipmwatch" support PMEM200 (2nd Gen Optane DCPMM) ?

And how could I use "ipmwatch" utility in my device? 

Many thanks for the help.

[SteveScargall · Accepted solution]

Hi csfrogy,

ipmwatch was written for Optane 100 PMem and hasn't been updated to support Optane 200. You should use the open-source PCM tool (pcm-memory) to view bandwidth and near-memory miss (Memory Mode).  

[csfrogy]

Hi SteveScargall, 

Thank you for offering your valuable advice and information.

[csfrogy]

Hi SteveScargall，

another question: 

Since the ipmwatch doesn't support Optane 200 and the PCM tool can only view bandwidth, how can I view the relationship between  media read/write(operations performed to the physical media) and the cpu read/write.

(I want to measure read/write amplification to physical media)

Many thanks for the help.

[SteveScargall]

If you or your company has an NDA with Intel, you can reach out through your Intel contact to request a tool that will collect the information. 

Alternatively, you can collect the performance data from the PMem modules using `ipmctl show -performance`:

# ipmctl show -performance
---DimmID=0x0001---
   MediaReads=0x00000000000000000000001570eb5eac
   MediaWrites=0x000000000000000000000012b723daac
   ReadRequests=0x000000000000000000000000049aab6b
   WriteRequests=0x0000000000000000000000000c7760af
   TotalMediaReads=0x000000000000000000001204fbe362f0
   TotalMediaWrites=0x0000000000000000000003ca773987fc
   TotalReadRequests=0x00000000000000000000016c58c6d361
   TotalWriteRequests=0x0000000000000000000000abb03f3bfc
---DimmID=0x0011---
[...snip...]

This approach isn't intended for frequent probing (ie: 1second), but you could write a shell script that will collect the data every 5seconds or more, then process the data into CSV or similar data that you could then graph if required.

[grayxu]

Confused about why

This approach isn't intended for frequent probing (ie: 1second)

---

As far as I know, PMWatch is dependent on libipmctl, don't they use same API or something? Are there any performance problems here? 

Thanks!