A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
-bash/zsh: blkparse command not found #Debian apt-get install blktrace #Ubuntu apt-get install blktrace #Kali Linux apt-get install blktrace #CentOS yum install blktrace #Fedora dnf install blktrace #Raspbian apt-get install blktrace
blkparse 工具将尝试对各种 CPU 各种设备的事件流相结合,而产生的事件信息的格式输出。具体来说,它将采用 blktrace
实用程序的(机器可读)输出,并将其转换为格式良好且易于阅读的形式。
blkparse [ options ]
-A hex-mask --set-mask=hex-mask Set filter mask to hex-mask, see blktrace (8) for masks -a mask --act-mask=mask Add mask to current filter, see blktrace (8) for masks -D dir --input-directory=dir Prepend dir to input file names -b batch --batch={batch} Standard input read batching -i file --input=file Specifies base name for input files -- default is device.blktrace.cpu. As noted above, specifying -i - runs in live mode with blktrace (reading data from standard in). -F typ,fmt --format=typ,fmt -f fmt --format-spec=fmt Sets output format (See OUTPUT DESCRIPTION AND FORMATTING for details.) The -f form specifies a format for all events The -F form allows one to specify a format for a specific event type. The single-character typ field is one of the action specifiers described in ACTION IDENTIFIERS. -M --no-msgs When -d is specified, this will stop messages from being output to the file. (Can seriously reduce the size of the resultant file when using the CFQ I/O scheduler.) -h --hash-by-name Hash processes by name, not by PID -o file --output=file Output file -O --no-text-output Do not produce text output, used for binary (-d) only -d file --dump-binary=file Binary output file -q --quiet Quiet mode -s --per-program-stats Displays data sorted by program -t --track-ios Display time deltas per IO -w span --stopwatch=span Display traces for the span specified -- where span can be: end-time -- Display traces from time 0 through end-time (in ns) or start:end-time -- Display traces from time start through end-time (in ns). -v --verbose More verbose marginal on marginal errors -V --version Display version Trace Actions The following trace actions are recognised: C -- complete A previously issued request has been completed. The output will detail the sector and size of that request, as well as the success or failure of it. D -- issued A request that previously resided on the block layer queue or in the i/o scheduler has been sent to the driver. I -- inserted A request is being sent to the i/o scheduler for addition to the internal queue and later service by the driver. The request is fully formed at this time. Q -- queued This notes intent to queue i/o at the given location. No real requests exists yet. B -- bounced The data pages attached to this bio are not reachable by the hardware and must be bounced to a lower memory location. This causes a big slowdown in i/o performance, since the data must be copied to/from kernel buffers. Usually this can be fixed with using better hardware -- either a better i/o controller, or a platform with an IOMMU. M -- back merge A previously inserted request exists that ends on the boundary of where this i/o begins, so the i/o scheduler can merge them together. F -- front merge Same as the back merge, except this i/o ends where a previously inserted requests starts. M --front or back merge One of the above M -- front or back merge One of the above. G -- get request To send any type of request to a block device, a struct request container must be allocated first. S -- sleep No available request structures were available, so the issuer has to wait for one to be freed. P -- plug When i/o is queued to a previously empty block device queue, Linux will plug the queue in anticipation of future ios being added before this data is needed. U -- unplug Some request data already queued in the device, start sending requests to the driver. This may happen automatically if a timeout period has passed (see next entry) or if a number of requests have been added to the queue. T -- unplug due to timer If nobody requests the i/o that was queued after plugging the queue, Linux will automatically unplug it after a defined period has passed. X -- split On raid or device mapper setups, an incoming i/o may straddle a device or internal zone and needs to be chopped up into smaller pieces for service. This may indicate a performance problem due to a bad setup of that raid/dm device, but may also just be part of normal boundary conditions. dm is notably bad at this and will clone lots of i/o. A -- remap For stacked devices, incoming i/o is remapped to device below it in the i/o stack. The remap action details what exactly is being remapped to what. Output Description and Formatting The output from blkparse can be tailored for specific use -- in particular, to ease parsing of output, and/or limit output fields to those the user wants to see. The data for fields which can be output include: a Action, a (small) string (1 or 2 characters) -- see table below for more details c CPU id C Command d RWBS field, a (small) string (1-3 characters) -- see section below for more details D 7-character string containing the major and minor numbers of the event's device (separated by a comma). e Error value m Minor number of event's device. M Major number of event's device. n Number of blocks N Number of bytes p Process ID P Display packet data -- series of hexadecimal values s Sequence numbers S Sector number t Time stamp (nanoseconds) T Time stamp (seconds) u Elapsed value in microseconds (-t command line option) U Payload unsigned integer Note that the user can optionally specify field display width, and optionally a left-aligned specifier. These precede field specifiers, with a '%' character, followed by the optional left-alignment specifier (-) followed by the width (a decimal number) and then the field. Thus, to specify the command in a 12-character field that is left aligned: -f "%-12C" Action Identifiers The following table shows the various actions which may be output: A IO was remapped to a different device B IO bounced C IO completion D IO issued to driver F IO front merged with request on queue G Get request I IO inserted onto request queue M IO back merged with request on queue P Plug request Q IO handled by request queue code S Sleep request T Unplug due to timeout U Unplug request X Split Rwbs Description This is a small string containing at least one character ('R' for read, 'W' for write, or 'D' for block discard operation), and optionally either a 'B' (for barrier operations) or 'S' (for synchronous operations). Default Output The standard header (or initial fields displayed) include: "%D %2c %8s %5T.%9t %5p %2a %3d" Breaking this down: %D Displays the event's device major/minor as: %3d,%-3d. %2c CPU ID (2-character field). %8s Sequence number %5T.%9t 5-character field for the seconds portion of the time stamp and a 9-character field for the nanoseconds in the time stamp. %5p 5-character field for the process ID. %2a 2-character field for one of the actions. %3d 3-character field for the RWBS data. Seeing this in action: 8,0 3 1 0.000000000 697 G W 223490 + 8 [kjournald] The header is the data in this line up to the 223490 (starting block). The default output for all event types includes this header. Default Output Per Action C -- complete If a payload is present, this is presented between parenthesis following the header, followed by the error value. If no payload is present, the sector and number of blocks are presented (with an intervening plus (+) character). If the -t option was specified, then the elapsed time is presented. In either case, it is followed by the error value for the completion. B -- bounced D -- issued I -- inserted Q -- queued If a payload is present, the number of payload bytes is output, followed by the payload in hexadecimal between parenthesis. If no payload is present, the sector and number of blocks are presented (with an intervening plus (+) character). If the -t option was specified, then the elapsed time is presented (in parenthesis). In either case, it is followed by the command associated with the event (surrounded by square brackets). F -- front merge G -- get request M -- back merge S -- sleep The starting sector and number of blocks is output (with an intervening plus (+) character), followed by the command associated with the event (surrounded by square brackets). P -- plug The command associated with the event (surrounded by square brackets) is output. U -- unplug T -- unplug due to timer The command associated with the event (surrounded by square brackets) is output, followed by the number of requests outstanding. X -- split The original starting sector followed by the new sector (separated by a slash (/) is output, followed by the command associated with the event (surrounded by square brackets). A -- remap Sector and length is output, along with the original device and sector offset.
blkparse 实例详见:blktrace 命令。