09-12-2013
Multithreading does not work that way; two cores can't cooperate to run a single-threaded program faster. Single-threaded programs will run slower on machines with lots of slower cores; we've had some puzzled folks ask us why their new machines have worse single-threaded benchmarks than their old ones.
But more cores means you can run more threads or processes at once without sharing time; more total work can be accomplished in the aggregate; but a program has to be designed with this in mind (or multiple instances of it run) to take advantage of this capability.
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LEARN ABOUT FREEBSD
crashinfo
CRASHINFO(8) BSD System Manager's Manual CRASHINFO(8)
NAME
crashinfo -- analyze a core dump of the operating system
SYNOPSIS
crashinfo [-d crashdir] [-n dumpnr] [-k kernel] [core]
DESCRIPTION
The crashinfo utility analyzes a core dump saved by savecore(8). It generates a text file containing the analysis in the same directory as
the core dump. For a given core dump file named vmcore.XX the generated text file will be named core.txt.XX.
By default, crashinfo analyzes the most recent core dump in the core dump directory. A specific core dump may be specified via either the
core or dumpnr arguments. Once crashinfo has located a core dump, it analyzes the core dump to determine the exact version of the kernel
that generated the core. It then looks for a matching kernel file under each of the subdirectories in /boot. The location of the kernel
file can also be explicitly provided via the kernel argument.
Once crashinfo has located a core dump and kernel, it uses several utilities to analyze the core including dmesg(8), fstat(1), iostat(8),
ipcs(1), kgdb(1), netstat(1), nfsstat(1), ps(1), pstat(8), and vmstat(8).
The options are as follows:
-d crashdir
Specify an alternate core dump directory. The default crash dump directory is /var/crash.
-n dumpnr
Use the core dump saved in vmcore.dumpnr instead of the latest core in the core dump directory.
-k kernel
Specify an explicit kernel file.
SEE ALSO
textdump(4), savecore(8)
HISTORY
The crashinfo utility appeared in FreeBSD 6.4.
BSD
June 28, 2008 BSD