[lttng-dev] UST lttng enable-event output improvement

Ettore Del Negro ettore at ettoredelnegro.me
Wed May 9 20:51:55 EDT 2012


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hello,
i have a simple question which may lead to a small user experience improvement:

> lttng create tsession
Session tsession created.
Traces will be written in .../lttng-traces/tsession-20120510-015819
> lttng enable-channel tchan -u -s tsession --subbuf-size=1024
UST channel tchan enabled for session tsession

a message stating that buffer size is set to a value different than default would be nice

> lttng enable-channel tchan -u -s tsession --subbuf-size=1022
UST channel tchan enabled for session tsession

What happens? Is it set to a value not power of 2? Is it set to the default value? (i guess the
latter).
The help says:
- --subbuf-size SIZE   Subbuffer size in bytes
      (default: 4096, kernel default: 262144)
      Needs to be a power of 2 for kernel and ust tracers

Thanks,
Ettore
-----BEGIN PGP SIGNATURE-----
Version: GnuPG/MacGPG2 v2.0.17 (Darwin)
Comment: GPGTools - http://gpgtools.org
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/
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=Q2pu
-----END PGP SIGNATURE-----



More information about the lttng-dev mailing list