Debugging and performance analysis tools (LINUX).

PROGRAM DEBUGGING AND PERFORMANCE TOOLS
=======================================
gdb          to attach to a running program:
                 $ gdb progname pid
ddd          graphical debugger
totalview    graphical debugger
gprof        where a program spends its time
strace       watch all syscalls a program makes
             if you didn't write the program, this
               is probably your best bet
time         summarize system resource usage (time,mem,I/O)
/usr/bin/time
gcov         profiling tool .. frequency of lines executed
               coverage testing - prove that every line is executed,
               branch probabilities, function summaries
             (example: 1.  gcc -fprofile-arcs -ftest-coverage x.c
                       2.  a.out
                       3.  gcov x.c
                       4.  cat x.c.gcov)
memprof      memory profiling (gui)
valgrind     memory debugger
ccmalloc     memory profiling
Electric Fence (compile with -lefence) - use for memory overruns
leak-analyze & LeakCheck - memory usage debugger
mpatrol & mptrace - debugging for dynamically allocated memory
purify       commercial package from Rational

SYSTEM PERFORMANCE ANALYSIS TOOLS
=================================
vmstat       virtual memory statistics
free         display free and used memory
top          display top cpu processes
files in /proc  files used as interface to kernel data structures
                examples: cpuinfo,stat
procinfo     display system status - gathered from /proc
ps           report process status
ksysguard    Task Manager and Performance Monitor
             like windows performance monitor 
             (process table and histogram of system load, memory)
sysstat
    sar      system activity information
             Statistics include I/O transfer rates, 
             paging activity, interrupts, network activity, 
             memory and swap space utilization, 
             CPU utilization, kernel activities and TTY statistics
    iostat   CPU and I/O stats
    mpstat   Processor related stats (works on SMP machines)

NETWORK
=======
ping         send echo request to network host
netstat      print net connections, routing tables, etc.
traceroute   print the route to a network host
dig (nslookup)
whois

FILE COMMANDS
=============
ldd 		print shared library dependencies