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perf-buildid-cache(1)
=====================

NAME
----
perf-buildid-cache - Manage build-id cache.

SYNOPSIS
--------
[verse]
'perf buildid-cache <options>'

DESCRIPTION
-----------
This command manages the build-id cache. It can add, remove, update and purge
files to/from the cache. In the future it should as well set upper limits for
the space used by the cache, etc.
This also scans the target binary for SDT (Statically Defined Tracing) and
record it along with the buildid-cache, which will be used by perf-probe.
For more details, see linkperf:perf-probe[1].

OPTIONS
-------
-a::
--add=::
        Add specified file to the cache.
-f::
--force::
	Don't complain, do it.
-k::
--kcore::
        Add specified kcore file to the cache. For the current host that is
        /proc/kcore which requires root permissions to read. Be aware that
        running 'perf buildid-cache' as root may update root's build-id cache
        not the user's. Use the -v option to see where the file is created.
        Note that the copied file contains only code sections not the whole core
        image. Note also that files "kallsyms" and "modules" must also be in the
        same directory and are also copied.  All 3 files are created with read
        permissions for root only. kcore will not be added if there is already a
        kcore in the cache (with the same build-id) that has the same modules at
        the same addresses. Use the -v option to see if a copy of kcore is
        actually made.
-r::
--remove=::
        Remove a cached binary which has same build-id of specified file
        from the cache.
-p::
--purge=::
        Purge all cached binaries including older caches which have specified
	path from the cache.
-P::
--purge-all::
	Purge all cached binaries. This will flush out entire cache.
-M::
--missing=::
	List missing build ids in the cache for the specified file.
-u::
--update=::
	Update specified file of the cache. Note that this doesn't remove
	older entires since those may be still needed for annotating old
	(or remote) perf.data. Only if there is already a cache which has
	exactly same build-id, that is replaced by new one. It can be used
	to update kallsyms and kernel dso to vmlinux in order to support
	annotation.
-l::
--list::
	List all valid binaries from cache.
-v::
--verbose::
	Be more verbose.

--target-ns=PID:
	Obtain mount namespace information from the target pid.  This is
	used when creating a uprobe for a process that resides in a
	different mount namespace from the perf(1) utility.

SEE ALSO
--------
linkperf:perf-record[1], linkperf:perf-report[1], linkperf:perf-buildid-list[1]