System panel

The System panel combines Linux CPU counters, load average, memory accounting, the SiMa MLA allocator report, the EV74 contiguous-memory pool, and periodic process snapshots.

CPU fields

Field	Source and calculation
CPU usage	Delta of aggregate /proc/stat CPU time between system samples. Busy percentage is 1 - idle_delta / total_delta; idle includes idle and I/O-wait fields.
CPU core N usage	Same delta calculation for each cpuN line in /proc/stat.
CPU load 1m	First value in /proc/loadavg; Linux's exponentially averaged count of runnable tasks and tasks in uninterruptible wait.
CPU load 1m percentage	load1 / logical_core_count × 100. It is a normalization for presentation and can exceed 100%.

CPU usage is immediate busy time over the latest sample window. Load is queued or waiting work over roughly one minute. High load with low CPU usage can indicate I/O waits or blocked work rather than compute saturation.

The first CPU sample has no previous counter baseline and is unavailable.

Per-core and process panels

The per-core bars show the latest cpuN utilization. Up/down selects a core.

The process table fields are:

Field	Meaning
PID	Linux process identifier.
CPU	Last processor number recorded in /proc/<pid>/stat; it is where the process was last observed, not an affinity guarantee.
%CPU	Process user+system CPU-tick delta divided by elapsed time. Approximately 100% represents one fully used logical CPU. Multithreaded processes can exceed 100%.
RSS MB	Resident pages from /proc/<pid>/stat multiplied by system page size and converted to MiB.
Name	Process command name from /proc/<pid>/stat.

Process data refreshes every five seconds. Sentinel retains only the top 64 processes globally, sorted by CPU and then RSS. When a selected core has no retained process, the UI falls back to showing the global retained list. Consequently, this panel is diagnostic rather than an exhaustive process accounting report.

Linux memory

used_bytes = MemTotal - MemAvailable
used_pct   = used_bytes / MemTotal × 100

MemAvailable comes from /proc/meminfo and estimates memory available for new work without swapping. This means cache that Linux can reclaim is not automatically treated as unavailable memory.

The MB display is calculated using 1024 × 1024 bytes, so it is technically MiB even though the UI label is MB.

MLA memory

Sentinel reads /dev/simaai-mem, finds Total allocated size:, parses the following hexadecimal byte count, and converts it to MiB.

This is MLA allocator memory currently allocated. It is not:

• MLA compute utilization;
• model FPS or latency;
• total physical DRAM use;
• a measurement of MLA 0.68V power.

If the device cannot be read or its text format is unrecognized, the value is unavailable rather than zero.

EV74 CMA memory

Sentinel reads CmaTotal and CmaFree from /proc/meminfo on every normal daemon sample and reports:

EV74 CMA used = CmaTotal - CmaFree

CmaTotal is the contiguous memory area reserved at boot. CmaFree is the currently unallocated portion of that reservation. The System tab displays the used value, while checkpoint recordings retain total, free, and used values. The Compare Runs tab can overlay EV74 CMA memory for selected runs.

This is an EV74 consumption proxy when EV74 is the consumer of the reserved CMA pool. Linux CMA is a shared kernel facility, so allocations by another driver can also reduce CmaFree; Sentinel cannot attribute those pages to an individual process from /proc/meminfo alone. If either field is absent, the derived used value is reported as unavailable rather than zero; any field that is present remains available on its own.

The boot reservation can be inspected separately with:

dmesg | grep -i cma