11-13-2014
Quote:
Originally Posted by
DGPickett
I wrote a "locality of reference" sort once: mmap64() the file and start sorting by making 2 lists of one line, then a linked list of 2 lines sorted, twice, and then merge them, then again, then merge the two sets of 4, etc.
This seems to be what is classically called
merge sort. In the wikipedia article there are also its Landau symbols for runtime estimates.
I hope this helps.
bakunin
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LEARN ABOUT CENTOS
stap-merge
STAP-MERGE(1) General Commands Manual STAP-MERGE(1)
NAME
stap-merge - systemtap per-cpu binary merger
SYNOPSIS
stap-merge [ OPTIONS ] [ INPUT FILENAMES ]
DESCRIPTION
The stap-merge executable applies when the -b option has been used while running a stap script. The -b option will generate files per-cpu,
based on the timestamp field. Then stap-merge will merge and sort through the per-cpu files based on the timestamp field.
OPTIONS
The systemtap merge executable supports the following options.
-v Verbose mode, displays three extra fields per set of collected data.
[cpunumber,sequencenumberofdata,thelengthofthedataset]
-o OUTPUT_FILENAME
Specify the name of the file you would like the output to be redirected into. If this option is not specified than the output will
be pushed to standard out.
EXAMPLES
$ stap -v -b -e 'probe syscall.open { printf("%s(%d) open
",
execname(), pid()) }'
This should result in several stpd_cpu files (each labled with a number representing which cpu the file was produced from).
$ stap-merge -v stpd_cpu0 stpd_cpu1
Running the stap-merge program in the same directory as the stap script earlier in the example, will produce an ordered sequence of packets
with the three part label for each set of data. This result will be pushed through the standard output. An output file could have been
specified using the "-o" option.
FILES
Important files and their corresponding paths can be located in the
stappaths(7) manual page.
SEE ALSO
stapprobes(3stap),
stappaths(7),
staprun(8),
stapvars(3stap),
stapex(3stap),
stap-server(8),
gdb(1)
BUGS
Use the Bugzilla link of the project web page or our mailing list. http://sourceware.org/systemtap/,<systemtap@sourceware.org>.
STAP-MERGE(1)