Hi guys,
I've noticed that, when I start 'fbtracemgr' session, server starts to
create files (fb_trace.{<UUID>.<n>) in /tmp/firebird (on Linux) and the
number of this files keeps growing and this files are not deleted after
trace session is terminated.
For example, I've started trace session with (same happens if I redirect
output to some file):
/opt/firebird/bin/fbtracemgr -u sysdba -p masterkey -SE service_mgr
-START -NAME fbt-trace -CONFIG $CFG >/dev/null
$CFG points to file with this content:
database
{
enabled = true
log_connections = false
log_transactions = false
log_statement_finish = true
log_errors = true
print_plan = true
explain_plan = false
print_perf = true
time_threshold = 0
max_sql_length = 8192
max_log_size = 100
}
services
{
}
After each minute there are around 150 new files (I'm tracing SQL on an
active database that has around 40 running sessions) and this keeps growing
until I terminate fbtracemg (with Ctrl-C) (i.e. after 10-15 minutes session
there are cca. 2000 files):
....
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002901
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002902
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002903
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002904
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002905
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002908
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002909
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002910
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002911
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002912
-rw-rw---- 1 firebird firebird 1048576 Jun 7 11:38
fb_trace.{59EE03A6-A2A6-40D4-BAB2-E4EE1D238DE1}.0002913
....
Documentation (https://firebirdsql.org/rlsnotesh/rnfb25-trace.html) states
that:
The output of a user session is stored in set of temporary files, each of 1
MB. Once a file has been completely read by the application, it is
automatically deleted. By default, the maximum total size of the output is
limited to 10 MB. It can be changed to a smaller or larger value using the
*MaxUserTraceLogSize* in firebird.conf.
Once the user trace session service has been started by the application,
the application has to read its output, using calls to *isc_service_query()*.
The service could be generating output faster than the application can read
it. If the total size of the output reaches the *MaxUserTraceLogSize* limit,
the engine automatically suspends the trace session. Once the application
has finished reading a file (a 1 MB part of the output) that file is
deleted, capacity is returned and the engine resumes the trace session
automatically.
Doesn't that mean that files should be kept on the filesystem only until
fbtracemsg was able to read them and then automatically deleted (so that
total size of them is constant if fbtracemsg manages to read them quickly
enough)?
I'm running: LI-V3.0.5.33125 Firebird 3.0
(*MaxUserTraceLogSize* is commented out in firebird.conf)
BR ,
Vladimir.
