Viewing Memory Access Analysis Results

Prerequisites

A memory access analysis task has been created and the analysis is complete.

Procedure

1. In the System Profiler area on the left, click the name of the target analysis task.

   The node list is displayed.

2. Click the name of the target node to view the analysis results.
   • Click the node name. The Summary tab page is displayed by default, as shown in Figure 1. For details about the parameters, see Table 1, Table 2, and Table 3.
     

     • The Summary page displays the summary data of each metric, including the system information, core cache miss, iCache bandwidth, dCache bandwidth, L3 hit rate and bandwidth, TLB miss, and DDR bandwidth.
     • Click View Average to view the details of each metric. Click to switch between the percentage view and MPKI view.
     • To collect L3 and DDR data, ensure that the OS is openEuler (kernel version: 4.19 or later) or CentOS 7.6 (kernel version: 4.14.0-115.el7a.0.1/4.15 or later). Only hisi_sccl events can be collected. You can run perf list|grep hisi_sccl to check whether hisi_sccl is supported. Kunpeng 916 servers do not support collection of such data.
     Figure 1 Summary
     
     Figure 2 Summary tab page – L3
     

     Table 1 Parameters in the System Information area

     Parameter	Description
     System Information
     Linux Kernel Version	Version of the Linux kernel.
     CPU Type	CPU type.
     NUMA NODE	NUMA node name.
     NUMA NODE0 CPUS	CPUs on NUMA node 0.
     NUMA NODE1 CPUS	CPUs on NUMA node 1.
     NUMA NODE2 CPUS	CPUs on NUMA node 2.
     NUMA NODE3 CPUS	CPUs on NUMA node 3.

   • Click the Cache Access tab page. The cache access line charts are displayed, as shown in Figure 3. For details about the parameters, see Table 2.
     

     • On the Cache Access tab page, the time sequence data of the access bandwidth and hit rates of L1, L2, L3, and TLB are shown in line charts. Click in the upper right corner to switch between the sequence diagram and table view.
     • You can select a CPU and type from the drop-down lists to view the corresponding line chart, or click to filter the CPU, type, bandwidth, and hit ratio.
     • You can specify the NUMA node and type to view the analysis result line charts of Bandwidth, Hit Rate, or Hit Bandwidth.
     • To collect L3 and DDR data, ensure that the OS is openEuler (kernel version: 4.19 or later) or CentOS 7.6 (kernel version: 4.14.0-115.el7a.0.1/4.15 or later). Only hisi_sccl events can be collected. You can run perf list|grep hisi_sccl to check whether hisi_sccl is supported. Kunpeng 916 servers do not support collection of such data.
     Figure 3 Cache access
     

     Table 2 Parameters in the Cache Access area

     Parameter	Description
     L1/L2/TLB Access Bandwidth and Hit Rate
     CPU	Select a CPU ID.
     Type	Select a data type.
     Bandwidth (MiB/s)	Access bandwidth.
     Hit Rate	Access hit rate.
     L3 Access Bandwidth and Hit Rate
     NUMA NODE	Select a NUMA node ID.
     Type	Access type.
     Hit Bandwidth (MiB/s)	Access hit bandwidth.
     Bandwidth (MiB/s)	Access bandwidth.
     Hit Rate	Access hit rate.

   • Click the DDR Access tab. The DDR access line charts are displayed, as shown in Figure 4. For details about the parameters, see Table 3.
     

     • On the DDR Access tab page, the time sequence data of the DDR access bandwidth and access times is shown in line charts. Click in the upper right corner to switch between the sequence diagram and table view.
     • In the DDR Access Bandwidth area, you can specify the NUMA node, DDR channel ID, and type to view the analysis result line charts.
     • In the DDR Access area, you can specify the NUMA node or type to view the analysis result line charts.
     • To collect L3 and DDR data, the OS must be openEuler (the kernel version must be 4.19 or later) or CentOS 7.6 (the kernel version must be 4.14.0-115.el7a.0.1/4.15 or later). Kunpeng 916 servers do not support collection of such data.
     Figure 4 DDR access
     

     Table 3 Parameters in the DDR Access area

     Parameter		Description
     DDR Access Bandwidth
     NUMA NODE		Select a NUMA node ID.
     DDR Controller ID		DDR controller ID.
     Type		DDR access type. The value can be Read DDR or Write DDR.
     Bandwidth (MiB/s)		DDR access bandwidth.
     Theoretical Maximum Bandwidth (MiB/s)		Theoretical maximum bandwidth of DDR access.
     Ratio (%)		Percentage of the current access bandwidth to the total access bandwidth
     DDR Access
     NUMA NODE		Select a NUMA node ID.
     Type		DDR access type. The value can be Read DDR or Write DDR.
     Total Accesses/s		Total number of DDR accesses per second.
     DDR Access	Local DDR Accesses/s (%)	Number of local DDR access times per second and the percentage of the number of local DDR access times to the total number of access times.
     	Cross-Die DDR Accesses/s (%)	Number of cross-die DDR access times per second and the percentage of the number of cross-die DDR access times to the total number of access times.
     	Cross-Chip DDR Accesses/s (%)	Number of cross-processor DDR access times per second and the percentage of the number of cross-processor DDR access times to the total number of access times.
     	DDR Access Times/s (%)	Sum of Local DDR Accesses/s (%), Cross-Die DDR Accesses/s (%), and Cross-Chip DDR Accesses/s (%), as well as the percentage of this sum to the total number of access times.

   • Click the Task Information tab to view the detailed configuration and sampling information about the task on the current node.
     

     If the task fails to be executed, the failure cause is displayed on the Task Information tab page.

     If some data fails to be collected but the overall task execution is not affected, you can view the exception message in Exception Information.

     Collection End Cause displays the reason why the data collection of the current task ends, for example, "Task collection times up" or "File size reaches the collection limit."