From mboxrd@z Thu Jan  1 00:00:00 1970
From: jdesfossez@efficios.com (Julien Desfossez)
Date: Sat, 28 May 2016 09:21:57 -0400
Subject: [lttng-dev] "lttng enable-channel --tracefile-size" bug
In-Reply-To: <CANgVouVswhgXmy=Dge5h2FA-7xsaJfDqOZ3=seG5dHjP=_4gmA@mail.gmail.com>
References: <CANgVouVswhgXmy=Dge5h2FA-7xsaJfDqOZ3=seG5dHjP=_4gmA@mail.gmail.com>
Message-ID: <57499B75.80203@efficios.com>

> Hi,
> it looks like for the "enable-channel" command, "tracefile-size" option
> doesn't take effect, bellow are all the options, the resulted files have
> the actual size the same as the size specified by subbuf-size option:
>  
> # lttng -V
> lttng (LTTng Trace Control) 2.7.1 - Herbe à Détourne
> 
> $ lttng enable-channel chan_name -u -s session_name --discard
> --num-subbuf 8 
>             --subbuf-size 32M --tracefile-size 8K --tracefile-count 8
> --buffers-pid

Yes, that is the expected behaviour, we work with packets (sub-buffers),
so the smallest unit we can store is the subbuf-size.

With 2.7.3 I get this warning when I try your command:
Warning: Tracefile size rounded up from (8192) to subbuffer size (33554432)

Julien