| chrt Set policy:
chrt [options] <priority> <command> [<arg>...]
chrt [options] --pid <priority> <pid>
Get policy:
chrt [options] -p <pid> Policy options:
-b, --batch set policy to SCHED_BATCH min/max priority : 0/0
-d, --deadline set policy to SCHED_DEADLINE min/max priority : 0/0
-f, --fifo set policy to SCHED_FIFO min/max priority : 1/99
-i, --idle set policy to SCHED_IDLE min/max priority : 0/0
-o, --other set policy to SCHED_OTHER min/max priority : 0/0
-r, --rr set policy to SCHED_RR (default) min/max priority : 1/99 Scheduling options:
-R, --reset-on-fork set SCHED_RESET_ON_FORK for FIFO or RR
-T, --sched-runtime <ns> runtime parameter for DEADLINE
-P, --sched-period <ns> period parameter for DEADLINE
-D, --sched-deadline <ns> deadline parameter for DEADLINE Other options:
-a, --all-tasks operate on all the tasks (threads) for a given pid
-m, --max show min and max valid priorities
-p, --pid operate on existing given pid
-v, --verbose display status information -h, --help display this help and exit
-V, --version output version information and exit |
strace [-CdffhiqrtttTvVwxxy] [-I n] [-e expr]... [-a column] [-o file] [-s strsize] [-P path]...
-p pid... / [-D] [-E var=val]... [-u username] PROG [ARGS]
or: strace -c[dfw] [-I n] [-e expr]... [-O overhead] [-S sortby]
-p pid... / [-D] [-E var=val]... [-u username] PROG [ARGS] Output format:
-a column alignment COLUMN for printing syscall results (default 40)
-i print instruction pointer at time of syscall
-o file send trace output to FILE instead of stderr
-q suppress messages about attaching, detaching, etc.
-r print relative timestamp
-s strsize limit length of print strings to STRSIZE chars (default 32)
-t print absolute timestamp
-tt print absolute timestamp with usecs
-T print time spent in each syscall
-x print non-ascii strings in hex
-xx print all strings in hex
-y print paths associated with file descriptor arguments
-yy print protocol specific information associated with socket file descriptors Statistics:
-c count time, calls, and errors for each syscall and report summary
-C like -c but also print regular output
-O overhead set overhead for tracing syscalls to OVERHEAD usecs
-S sortby sort syscall counts by: time, calls, name, nothing (default time)
-w summarise syscall latency (default is system time) Filtering:
-e expr a qualifying expression: option=[!]all or option=[!]val1[,val2]...
options: trace, abbrev, verbose, raw, signal, read, write
-P path trace accesses to path Tracing:
-b execve detach on execve syscall
-D run tracer process as a detached grandchild, not as parent
-f follow forks
-ff follow forks with output into separate files
-I interruptible
1: no signals are blocked
2: fatal signals are blocked while decoding syscall (default)
3: fatal signals are always blocked (default if '-o FILE PROG')
4: fatal signals and SIGTSTP (^Z) are always blocked
(useful to make 'strace -o FILE PROG' not stop on ^Z) Startup:
-E var remove var from the environment for command
-E var=val put var=val in the environment for command
-p pid trace process with process id PID, may be repeated
-u username run command as username handling setuid and/or setgid Miscellaneous:
-d enable debug output to stderr
-v verbose mode: print unabbreviated argv, stat, termios, etc. args
-h print help message
-V print version |
| getconf 本身是个ELF可执行文件，用于获取系统信息
用法
getconf -a可以获取全部系统信息
对于这个命令，记住几个常用的信息获取方法就行
getconf PAGE_SIZE 查看系统内存分页大小
getconf LONG_BIT 看linux是32位还是64位最简单的方法
_CS_PATH Value for the PATH environment variable used to find commands.
ARG_MAX Maximum length, in bytes, of the arguments for one of the exec subroutines, including environment data.
BC_BASE_MAX Maximum value allowed for the obase variable with the bc command.
BC_DIM_MAX Maximum number of elements permitted in an array by the bc command.
BC_SCALE_MAX Maximum value allowed for the scale variable with the bc command.
BC_STRING_MAX Maximum length of a string constant accepted by the bc command.
CHARCLASS_NAME_MAX Maximum number of bytes in a character class name.
CHAR_BIT Number of bits in a type character.
CHAR_MAX Maximum value of a type character.
CHAR_MIN Minimum value of a type character.
CHILD_MAX Maximum number of simultaneous processes for each real user ID.
CLK_TCK Number of clock ticks per second returned by the time subroutine.
COLL_WEIGHTS_MAX Maximum number of weights that can be assigned to an entry in the LC_COLLATE locale stanza in a locale-definition file.
CS_PATH Value of the PATH environment variable used to find commands.
EXPR_NEST_MAX Maximum number of expressions that can be nested within parentheses by the expr command.
INT_MAX Maximum value of a type int.
INT_MIN Minimum value of a type int.
LINE_MAX Maximum length, in bytes, of a command's input line (either standard input or another file) when the utility is described as processing text files. The length includes room for the trailing new-line character.
LONG_BIT Number of bits in a type long int.
LONG_MAX Maximum value of a type long int.
LONG_MIN Minimum value of a type long int.
MB_LEN_MAX Maximum number of bytes in a character for any supported locale.
NGROUPS_MAX Maximum number of simultaneous supplementary group IDs for each process.
NL_ARGMAX Maximum value of digit in calls to the printf and scanf subroutines.
NL_LANGMAX Maximum number of bytes in a LANG name.
NL_MSGMAX Maximum message number.
NL_NMAX Maximum number of bytes in an N-to-1 collation mapping.
NL_SETMAX Maximum set number.
NL_TEXTMAX Maximum number of bytes in a message string.
NZERO Default process priority.
OPEN_MAX Maximum number of files that one process can have open at one time.
PATH Sequence of colon-separated path prefixes used to find commands.
RE_DUP_MAX Maximum number of repeated occurrences of a regular expression permitted when using the interval-notation parameters, such as the m and n parameters with the ed command.
SCHAR_MAX Maximum value of a type signed char.
SCHAR_MIN Minimum value of a type signed char.
SHRT_MAX Maximum value of a type short.
SHRT_MIN Minimum value of a type short.
SSIZE_MAX Maximum value of an object of type ssize_t.
STREAM_MAX Number of streams that one process can have open at one time.
TMP_MAX Minimum number of unique path names generated by the tmpnam subroutine. Maximum number of times an application can reliably call the tmpnam subroutine.
TZNAME_MAX Maximum number of bytes supported for the name of a time zone (not the length of the TZ environment variable).
UCHAR_MAX Maximum value of a type unsigned char.
UINT_MAX Maximum value of a type unsigned int.
ULONG_MAX Maximum value of a type unsigned long int.
USHRT_MAX Maximum value of a type unsigned short int.
WORD_BIT Number of bits in a word or type int |
ltrace [option ...] [command [arg ...]] Trace library calls of a given program. -a, --align=COLUMN align return values in a secific column.
-A MAXELTS maximum number of array elements to print.
-b, --no-signals don't print signals.
-c count time and calls, and report a summary on exit.
-C, --demangle decode low-level symbol names into user-level names.
-D, --debug=MASK enable debugging (see -Dh or --debug=help).
-Dh, --debug=help show help on debugging.
-e FILTER modify which library calls to trace.
-f trace children (fork() and clone()).
-F, --config=FILE load alternate configuration file (may be repeated).
-h, --help display this help and exit.
-i print instruction pointer at time of library call.
-l, --library=LIBRARY_PATTERN only trace symbols implemented by this library.
-L do NOT display library calls.
-n, --indent=NR indent output by NR spaces for each call level nesting.
-o, --output=FILENAME write the trace output to file with given name.
-p PID attach to the process with the process ID pid.
-r print relative timestamps.
-s STRSIZE specify the maximum string size to print.
-S trace system calls as well as library calls.
-t, -tt, -ttt print absolute timestamps.
-T show the time spent inside each call.
-u USERNAME run command with the userid, groupid of username.
-V, --version output version information and exit.
-w, --where=NR print backtrace showing NR stack frames at most.
-x FILTER modify which static functions to trace. |