---
name: "ppchcalls-bpfcc"
section: "8"
platform: "linux"
package: "bpfcc-tools"
version: "0.31.0+ds-7"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/ppchcalls-bpfcc"
---

# ppchcalls-bpfcc(8)

Summarize ppc hcall counts and latencies.

## NAME

ppchcalls - Summarize ppc hcall counts and latencies.

## SYNOPSIS

**ppchcalls \[-h\] \[-p PID\] \[-t TID\] \[-i INTERVAL\] \[-d DURATION\] \[-T TOP\] \[-x\] \[-e ERRNO\] \[-L\] \[-m\] \[-P\] \[-l\] \[--hcall HCALL\]**

## DESCRIPTION

This tool traces hcall entry and exit raw tracepoints and summarizes either the number of hcalls of each type, or the number of hcalls per process. It can also collect min, max and average latency for each hcall or each process.

Since this uses BPF, only the root user can use this tool.

## REQUIREMENTS

CONFIG\_BPF and bcc. Linux 4.17+ is required to attach a BPF program to the raw\_hcalls:hcall\_{enter,exit} tracepoints, used by this tool.

## OPTIONS

- \-h

  Print usage message.

- \-p PID

  Trace only this process.

- \-t TID

  Trace only this thread.

- \-i INTERVAL

  Print the summary at the specified interval (in seconds).

- \-d DURATION

  Total duration of trace (in seconds).

- \-T TOP

  Print only this many entries. Default: 10.

- \-x

  Trace only failed hcalls (i.e., the return value from the hcall was \< 0).

- \-e ERRNO

  Trace only hcalls that failed with that error (e.g. -e EPERM or -e 1).

- \-m

  Display times in milliseconds. Default: microseconds.

- \-P

  Summarize by process and not by hcall.

- \-l

  List the hcalls recognized by the tool (hard-coded list). Hcalls beyond this list will still be displayed, as "\[unknown: nnn\]" where nnn is the hcall number.

- \--hcall HCALL

  Trace this hcall only (use option -l to get all recognized hcalls).

## EXAMPLES

- Summarize all hcalls by hcall:

  \# **ppchcalls**

- Summarize all hcalls by process:

  \# **ppchcalls -P**

- Summarize only failed hcalls:

  \# **ppchcalls -x**

- Summarize only hcalls that failed with EPERM:

  \# **ppchcalls -e EPERM**

- Trace PID 181 only:

  \# **ppchcalls -p 181**

- Summarize hcalls counts and latencies:

  \# **ppchcalls -L**

## FIELDS

- PID

  Process ID

- COMM

  Process name

- HCALL

  Hcall name, or "\[unknown: nnn\]" for hcalls that aren't recognized

- COUNT

  The number of events

- MIN

  The minimum elapsed time (in us or ms)

- MAX

  The maximum elapsed time (in us or ms)

- AVG

  The average elapsed time (in us or ms)

## OVERHEAD

For most applications, the overhead should be manageable if they perform 1000's or even 10,000's of hcalls per second. For higher rates, the overhead may become considerable.

## SOURCE

This is from bcc.

-

  https://github.com/iovisor/bcc

Also look in the bcc distribution for a companion \_examples.txt file containing example usage, output, and commentary for this tool.

## OS

Linux

## STABILITY

Unstable - in development.

## AUTHOR

Harsh Prateek Bora

## SEE ALSO

syscount(8)