How do I read a perf data file?

How do I read a perf data file?

There is builtin perf. data parser and printer in perf tool of linux tools with subcommand “script”. perf-script – Read perf. data (created by perf record) and display trace output This command reads the input file and displays the trace recorded.

How do you annotate perf?

You can also annotate using the perf top command. Run the perf top command and press ‘a’ on any particular symbol that you want to annotate. It also dynamically updates data at a fixed interval.

What is perf report?

perf report is able to auto-detect whether a perf. data file contains branch stacks and it will automatically switch to the branch view mode, unless –no-branch-stack is used. –branch-history Add the addresses of sampled taken branches to the callstack. This allows to examine the path the program took to each sample.

Does perf use Ftrace?

perf ftrace is a simple wrapper for kernel’s ftrace functionality, and only supports single thread tracing now.

What is perf file?

Perf consists of kernel code and an userspace tool. The tool records the data to an file which can be analyzed later. Understanding this data format is necessary for individual software performance analysis. This report provides information about the data structures used to read the data file.

What is perf tool?

perf (sometimes called perf_events or perf tools, originally Performance Counters for Linux, PCL) is a performance analyzing tool in Linux, available from Linux kernel version 2.6. 31 in 2009.

What is perf overhead?

The overhead can be shown in two columns as ‘Children’ and ‘Self’ when perf collects callchains. The ‘self’ overhead is simply calculated by adding all period values of the entry – usually a function (symbol). This is the value that perf shows traditionally and sum of all the ‘self’ overhead values should be 100%.

What is perf top?

DESCRIPTION top This command generates and displays a performance counter profile in real time.

What is perf used for?

Perf is a profiler tool for Linux 2.6+ based systems that abstracts away CPU hardware differences in Linux performance measurements and presents a simple commandline interface. Perf is based on the perf_events interface exported by recent versions of the Linux kernel.

What is perf kernel?

What is Python perf?

The python-perf package contains a module that permits applications written in the Python programming language to use the interface to manipulate perf events.

What is the perf command?

The perf command is used as a primary interface to the Linux kernel performance monitoring capabilities and can record CPU performance counters and trace points.

What does the acronym perf mean?


Acronym Definition
PERF Performance
PERF Perform
PERF Perforated
PERF Perforation (stamp collecting)

How does a perf tool work?

Perf works on the Model Specific Registers of your CPU for measurements like cycles or branch-misses or so. A special Part called PMU(Performance Measurement Unit) is counting all kinds of events.

What is perf command?

How does perf work Linux?

Perf overview Perf is a facility comprised of kernel infrastructure for gathering various events and userspace tool to get gathered data from the kernel and analyze it. It is like a gprof, but it is non-invasive, low-overhead and profile the whole stack, including your app, libraries, system calls AND kernel with CPU!

How does perf work in Indiana?

Member Contributions PERF-covered employees are required by state law to contribute three percent of their gross wages (regular and overtime pay) to the Fund. Effective July 1, 1986, Indiana law required the state of Indiana to pay the three percent contributions for state employees as part of a wage adjustment.

How do perf events work?

When can I retire with perf?

age 65
Normally participants are eligible for full retirement benefits at age 65 with 10 or more years of service in a PERF plan. Individuals who have worked in a PERF-eligible position for 15 or more years are eligible for early retirement benefits.

What does vested mean perf?

Vested in the PERF/TRF Hybrid plan means a member has at least 10 years of covered service (certain elected officials have eight-year vesting). You earn service by working in a PERF/ TRF-covered position, but may also be eligible for service credit if you have military service leave or other authorized leaves.