#Monitoring your GlusterFS Workload
You can monitor the GlusterFS volumes on different parameters.
Monitoring volumes helps in capacity planning and performance tuning
tasks of the GlusterFS volume. Using these information, you can identify
and troubleshoot issues.
You can use Volume Top and Profile commands to view the performance and
identify bottlenecks/hotspots of each brick of a volume. This helps
system administrators to get vital performance information whenever
performance needs to be probed.
You can also perform statedump of the brick processes and nfs server
process of a volume, and also view volume status and volume information.
##Running GlusterFS Volume Profile Command
GlusterFS Volume Profile command provides an interface to get the
per-brick I/O information for each File Operation (FOP) of a volume. The
per brick information helps in identifying bottlenecks in the storage
system.
This section describes how to run GlusterFS Volume Profile command by
performing the following operations:
- [Start Profiling](#start-profiling)
- [Displaying the I/0 Information](#displaying-io)
- [Stop Profiling](#stop-profiling)
###Start Profiling
You must start the Profiling to view the File Operation information for
each brick.
To start profiling, use following command:
`# gluster volume profile start `
For example, to start profiling on test-volume:
# gluster volume profile test-volume start
Profiling started on test-volume
When profiling on the volume is started, the following additional
options are displayed in the Volume Info:
diagnostics.count-fop-hits: on
diagnostics.latency-measurement: on
###Displaying the I/0 Information
You can view the I/O information of each brick by using the following command:
`# gluster volume profile info`
For example, to see the I/O information on test-volume:
# gluster volume profile test-volume info
Brick: Test:/export/2
Cumulative Stats:
Block 1b+ 32b+ 64b+
Size:
Read: 0 0 0
Write: 908 28 8
Block 128b+ 256b+ 512b+
Size:
Read: 0 6 4
Write: 5 23 16
Block 1024b+ 2048b+ 4096b+
Size:
Read: 0 52 17
Write: 15 120 846
Block 8192b+ 16384b+ 32768b+
Size:
Read: 52 8 34
Write: 234 134 286
Block 65536b+ 131072b+
Size:
Read: 118 622
Write: 1341 594
%-latency Avg- Min- Max- calls Fop
latency Latency Latency
___________________________________________________________
4.82 1132.28 21.00 800970.00 4575 WRITE
5.70 156.47 9.00 665085.00 39163 READDIRP
11.35 315.02 9.00 1433947.00 38698 LOOKUP
11.88 1729.34 21.00 2569638.00 7382 FXATTROP
47.35 104235.02 2485.00 7789367.00 488 FSYNC
------------------
------------------
Duration : 335
BytesRead : 94505058
BytesWritten : 195571980
###Stop Profiling
You can stop profiling the volume, if you do not need profiling
information anymore.
Stop profiling using the following command:
`# gluster volume profile stop`
For example, to stop profiling on test-volume:
`# gluster volume profile stop`
`Profiling stopped on test-volume`
##Running GlusterFS Volume TOP Command
GlusterFS Volume Top command allows you to view the glusterfs bricks’
performance metrics like read, write, file open calls, file read calls,
file write calls, directory open calls, and directory real calls. The
top command displays up to 100 results.
This section describes how to run and view the results for the following
GlusterFS Top commands:
- [Viewing Open fd Count and Maximum fd Count](#open-fd-count)
- [Viewing Highest File Read Calls](#file-read)
- [Viewing Highest File Write Calls](#file-write)
- [Viewing Highest Open Calls on Directories](#open-dir)
- [Viewing Highest Read Calls on Directory](#read-dir)
- [Viewing List of Read Performance on each Brick](#read-perf)
- [Viewing List of Write Performance on each Brick](#write-perf)
###Viewing Open fd Count and Maximum fd Count
You can view both current open fd count (list of files that are
currently the most opened and the count) on the brick and the maximum
open fd count (count of files that are the currently open and the count
of maximum number of files opened at any given point of time, since the
servers are up and running). If the brick name is not specified, then
open fd metrics of all the bricks belonging to the volume will be
displayed.
- View open fd count and maximum fd count using the following command:
`# gluster volume top open [brick ] [list-cnt ]`
For example, to view open fd count and maximum fd count on brick
server:/export of test-volume and list top 10 open calls:
`# gluster volume top open brick list-cnt `
`Brick: server:/export/dir1 `
`Current open fd's: 34 Max open fd's: 209 `
==========Open file stats========
open file name
call count
2 /clients/client0/~dmtmp/PARADOX/
COURSES.DB
11 /clients/client0/~dmtmp/PARADOX/
ENROLL.DB
11 /clients/client0/~dmtmp/PARADOX/
STUDENTS.DB
10 /clients/client0/~dmtmp/PWRPNT/
TIPS.PPT
10 /clients/client0/~dmtmp/PWRPNT/
PCBENCHM.PPT
9 /clients/client7/~dmtmp/PARADOX/
STUDENTS.DB
9 /clients/client1/~dmtmp/PARADOX/
STUDENTS.DB
9 /clients/client2/~dmtmp/PARADOX/
STUDENTS.DB
9 /clients/client0/~dmtmp/PARADOX/
STUDENTS.DB
9 /clients/client8/~dmtmp/PARADOX/
STUDENTS.DB
###Viewing Highest File Read Calls
You can view highest read calls on each brick. If brick name is not
specified, then by default, list of 100 files will be displayed.
- View highest file Read calls using the following command:
`# gluster volume top read [brick ] [list-cnt ] `
For example, to view highest Read calls on brick server:/export of
test-volume:
`# gluster volume top read brick list-cnt `
`Brick:` server:/export/dir1
==========Read file stats========
read filename
call count
116 /clients/client0/~dmtmp/SEED/LARGE.FIL
64 /clients/client0/~dmtmp/SEED/MEDIUM.FIL
54 /clients/client2/~dmtmp/SEED/LARGE.FIL
54 /clients/client6/~dmtmp/SEED/LARGE.FIL
54 /clients/client5/~dmtmp/SEED/LARGE.FIL
54 /clients/client0/~dmtmp/SEED/LARGE.FIL
54 /clients/client3/~dmtmp/SEED/LARGE.FIL
54 /clients/client4/~dmtmp/SEED/LARGE.FIL
54 /clients/client9/~dmtmp/SEED/LARGE.FIL
54 /clients/client8/~dmtmp/SEED/LARGE.FIL
###Viewing Highest File Write Calls
You can view list of files which has highest file write calls on each
brick. If brick name is not specified, then by default, list of 100
files will be displayed.
- View highest file Write calls using the following command:
`# gluster volume top write [brick ] [list-cnt ] `
For example, to view highest Write calls on brick server:/export of
test-volume:
`# gluster volume top write brick list-cnt `
`Brick: server:/export/dir1 `
==========Write file stats========
write call count filename
83 /clients/client0/~dmtmp/SEED/LARGE.FIL
59 /clients/client7/~dmtmp/SEED/LARGE.FIL
59 /clients/client1/~dmtmp/SEED/LARGE.FIL
59 /clients/client2/~dmtmp/SEED/LARGE.FIL
59 /clients/client0/~dmtmp/SEED/LARGE.FIL
59 /clients/client8/~dmtmp/SEED/LARGE.FIL
59 /clients/client5/~dmtmp/SEED/LARGE.FIL
59 /clients/client4/~dmtmp/SEED/LARGE.FIL
59 /clients/client6/~dmtmp/SEED/LARGE.FIL
59 /clients/client3/~dmtmp/SEED/LARGE.FIL
###Viewing Highest Open Calls on Directories
You can view list of files which has highest open calls on directories
of each brick. If brick name is not specified, then the metrics of all
the bricks belonging to that volume will be displayed.
- View list of open calls on each directory using the following
command:
`# gluster volume top opendir [brick ] [list-cnt ] `
For example, to view open calls on brick server:/export/ of
test-volume:
`# gluster volume top opendir brick list-cnt `
`Brick: server:/export/dir1 `
==========Directory open stats========
Opendir count directory name
1001 /clients/client0/~dmtmp
454 /clients/client8/~dmtmp
454 /clients/client2/~dmtmp
454 /clients/client6/~dmtmp
454 /clients/client5/~dmtmp
454 /clients/client9/~dmtmp
443 /clients/client0/~dmtmp/PARADOX
408 /clients/client1/~dmtmp
408 /clients/client7/~dmtmp
402 /clients/client4/~dmtmp
###Viewing Highest Read Calls on Directory
You can view list of files which has highest directory read calls on
each brick. If brick name is not specified, then the metrics of all the
bricks belonging to that volume will be displayed.
- View list of highest directory read calls on each brick using the
following command:
`# gluster volume top readdir [brick ] [list-cnt ] `
For example, to view highest directory read calls on brick
server:/export of test-volume:
`# gluster volume top readdir brick list-cnt `
`Brick: `
==========Directory readdirp stats========
readdirp count directory name
1996 /clients/client0/~dmtmp
1083 /clients/client0/~dmtmp/PARADOX
904 /clients/client8/~dmtmp
904 /clients/client2/~dmtmp
904 /clients/client6/~dmtmp
904 /clients/client5/~dmtmp
904 /clients/client9/~dmtmp
812 /clients/client1/~dmtmp
812 /clients/client7/~dmtmp
800 /clients/client4/~dmtmp
###Viewing List of Read Performance on each Brick
You can view the read throughput of files on each brick. If brick name
is not specified, then the metrics of all the bricks belonging to that
volume will be displayed. The output will be the read throughput.
==========Read throughput file stats========
read filename Time
through
put(MBp
s)
2570.00 /clients/client0/~dmtmp/PWRPNT/ -2011-01-31
TRIDOTS.POT 15:38:36.894610
2570.00 /clients/client0/~dmtmp/PWRPNT/ -2011-01-31
PCBENCHM.PPT 15:38:39.815310
2383.00 /clients/client2/~dmtmp/SEED/ -2011-01-31
MEDIUM.FIL 15:52:53.631499
2340.00 /clients/client0/~dmtmp/SEED/ -2011-01-31
MEDIUM.FIL 15:38:36.926198
2299.00 /clients/client0/~dmtmp/SEED/ -2011-01-31
LARGE.FIL 15:38:36.930445
2259.00 /clients/client0/~dmtmp/PARADOX/ -2011-01-31
COURSES.X04 15:38:40.549919
2221.00 /clients/client0/~dmtmp/PARADOX/ -2011-01-31
STUDENTS.VAL 15:52:53.298766
2221.00 /clients/client3/~dmtmp/SEED/ -2011-01-31
COURSES.DB 15:39:11.776780
2184.00 /clients/client3/~dmtmp/SEED/ -2011-01-31
MEDIUM.FIL 15:39:10.251764
2184.00 /clients/client5/~dmtmp/WORD/ -2011-01-31
BASEMACH.DOC 15:39:09.336572
This command will initiate a dd for the specified count and block size
and measures the corresponding throughput.
- View list of read performance on each brick using the following
command:
`# gluster volume top read-perf [bs count ] [brick ] [list-cnt ]`
For example, to view read performance on brick server:/export/ of
test-volume, 256 block size of count 1, and list count 10:
`# gluster volume top read-perf bs 256 count 1 brick list-cnt `
`Brick: server:/export/dir1 256 bytes (256 B) copied, Throughput: 4.1 MB/s `
==========Read throughput file stats========
read filename Time
through
put(MBp
s)
2912.00 /clients/client0/~dmtmp/PWRPNT/ -2011-01-31
TRIDOTS.POT 15:38:36.896486
2570.00 /clients/client0/~dmtmp/PWRPNT/ -2011-01-31
PCBENCHM.PPT 15:38:39.815310
2383.00 /clients/client2/~dmtmp/SEED/ -2011-01-31
MEDIUM.FIL 15:52:53.631499
2340.00 /clients/client0/~dmtmp/SEED/ -2011-01-31
MEDIUM.FIL 15:38:36.926198
2299.00 /clients/client0/~dmtmp/SEED/ -2011-01-31
LARGE.FIL 15:38:36.930445
2259.00 /clients/client0/~dmtmp/PARADOX/ -2011-01-31
COURSES.X04 15:38:40.549919
2221.00 /clients/client9/~dmtmp/PARADOX/ -2011-01-31
STUDENTS.VAL 15:52:53.298766
2221.00 /clients/client8/~dmtmp/PARADOX/ -2011-01-31
COURSES.DB 15:39:11.776780
2184.00 /clients/client3/~dmtmp/SEED/ -2011-01-31
MEDIUM.FIL 15:39:10.251764
2184.00 /clients/client5/~dmtmp/WORD/ -2011-01-31
BASEMACH.DOC 15:39:09.336572
###Viewing List of Write Performance on each Brick
You can view list of write throughput of files on each brick. If brick
name is not specified, then the metrics of all the bricks belonging to
that volume will be displayed. The output will be the write throughput.
This command will initiate a dd for the specified count and block size
and measures the corresponding throughput. To view list of write
performance on each brick:
- View list of write performance on each brick using the following
command:
`# gluster volume top write-perf [bs count ] [brick ] [list-cnt ] `
For example, to view write performance on brick server:/export/ of
test-volume, 256 block size of count 1, and list count 10:
`# gluster volume top write-perf bs 256 count 1 brick list-cnt `
`Brick`: server:/export/dir1
`256 bytes (256 B) copied, Throughput: 2.8 MB/s `
==========Write throughput file stats========
write filename Time
throughput
(MBps)
1170.00 /clients/client0/~dmtmp/SEED/ -2011-01-31
SMALL.FIL 15:39:09.171494
1008.00 /clients/client6/~dmtmp/SEED/ -2011-01-31
LARGE.FIL 15:39:09.73189
949.00 /clients/client0/~dmtmp/SEED/ -2011-01-31
MEDIUM.FIL 15:38:36.927426
936.00 /clients/client0/~dmtmp/SEED/ -2011-01-31
LARGE.FIL 15:38:36.933177
897.00 /clients/client5/~dmtmp/SEED/ -2011-01-31
MEDIUM.FIL 15:39:09.33628
897.00 /clients/client6/~dmtmp/SEED/ -2011-01-31
MEDIUM.FIL 15:39:09.27713
885.00 /clients/client0/~dmtmp/SEED/ -2011-01-31
SMALL.FIL 15:38:36.924271
528.00 /clients/client5/~dmtmp/SEED/ -2011-01-31
LARGE.FIL 15:39:09.81893
516.00 /clients/client6/~dmtmp/ACCESS/ -2011-01-31
FASTENER.MDB 15:39:01.797317
##Displaying Volume Information
You can display information about a specific volume, or all volumes, as
needed.
- Display information about a specific volume using the following
command:
`# gluster volume info ``VOLNAME`
For example, to display information about test-volume:
# gluster volume info test-volume
Volume Name: test-volume
Type: Distribute
Status: Created
Number of Bricks: 4
Bricks:
Brick1: server1:/exp1
Brick2: server2:/exp2
Brick3: server3:/exp3
Brick4: server4:/exp4
- Display information about all volumes using the following command:
`# gluster volume info all`
# gluster volume info all
Volume Name: test-volume
Type: Distribute
Status: Created
Number of Bricks: 4
Bricks:
Brick1: server1:/exp1
Brick2: server2:/exp2
Brick3: server3:/exp3
Brick4: server4:/exp4
Volume Name: mirror
Type: Distributed-Replicate
Status: Started
Number of Bricks: 2 X 2 = 4
Bricks:
Brick1: server1:/brick1
Brick2: server2:/brick2
Brick3: server3:/brick3
Brick4: server4:/brick4
Volume Name: Vol
Type: Distribute
Status: Started
Number of Bricks: 1
Bricks:
Brick: server:/brick6
##Performing Statedump on a Volume
Statedump is a mechanism through which you can get details of all
internal variables and state of the glusterfs process at the time of
issuing the command.You can perform statedumps of the brick processes
and nfs server process of a volume using the statedump command. The
following options can be used to determine what information is to be
dumped:
- **mem** - Dumps the memory usage and memory pool details of the
bricks.
- **iobuf** - Dumps iobuf details of the bricks.
- **priv** - Dumps private information of loaded translators.
- **callpool** - Dumps the pending calls of the volume.
- **fd** - Dumps the open fd tables of the volume.
- **inode** - Dumps the inode tables of the volume.
**To display volume statedump**
- Display statedump of a volume or NFS server using the following
command:
`# gluster volume statedump [nfs] [all|mem|iobuf|callpool|priv|fd|inode]`
For example, to display statedump of test-volume:
# gluster volume statedump test-volume
Volume statedump successful
The statedump files are created on the brick servers in the` /tmp`
directory or in the directory set using `server.statedump-path`
volume option. The naming convention of the dump file is
`..dump`.
- By defult, the output of the statedump is stored at
` /tmp/` file on that particular server. Change
the directory of the statedump file using the following command:
`# gluster volume set server.statedump-path `
For example, to change the location of the statedump file of
test-volume:
# gluster volume set test-volume server.statedump-path /usr/local/var/log/glusterfs/dumps/
Set volume successful
You can view the changed path of the statedump file using the
following command:
`# gluster volume info `
##Displaying Volume Status
You can display the status information about a specific volume, brick or
all volumes, as needed. Status information can be used to understand the
current status of the brick, nfs processes, and overall file system.
Status information can also be used to monitor and debug the volume
information. You can view status of the volume along with the following
details:
- **detail** - Displays additional information about the bricks.
- **clients** - Displays the list of clients connected to the volume.
- **mem** - Displays the memory usage and memory pool details of the
bricks.
- **inode** - Displays the inode tables of the volume.
- **fd** - Displays the open fd (file descriptors) tables of the
volume.
- **callpool** - Displays the pending calls of the volume.
**To display volume status**
- Display information about a specific volume using the following
command:
`# gluster volume status [all| []] [detail|clients|mem|inode|fd|callpool]`
For example, to display information about test-volume:
# gluster volume status test-volume
STATUS OF VOLUME: test-volume
BRICK PORT ONLINE PID
--------------------------------------------------------
arch:/export/1 24009 Y 22445
--------------------------------------------------------
arch:/export/2 24010 Y 22450
- Display information about all volumes using the following command:
`# gluster volume status all`
# gluster volume status all
STATUS OF VOLUME: volume-test
BRICK PORT ONLINE PID
--------------------------------------------------------
arch:/export/4 24010 Y 22455
STATUS OF VOLUME: test-volume
BRICK PORT ONLINE PID
--------------------------------------------------------
arch:/export/1 24009 Y 22445
--------------------------------------------------------
arch:/export/2 24010 Y 22450
- Display additional information about the bricks using the following
command:
`# gluster volume status detail`
For example, to display additional information about the bricks of
test-volume:
# gluster volume status test-volume details
STATUS OF VOLUME: test-volume
-------------------------------------------
Brick : arch:/export/1
Port : 24009
Online : Y
Pid : 16977
File System : rootfs
Device : rootfs
Mount Options : rw
Disk Space Free : 13.8GB
Total Disk Space : 46.5GB
Inode Size : N/A
Inode Count : N/A
Free Inodes : N/A
Number of Bricks: 1
Bricks:
Brick: server:/brick6
- Display the list of clients accessing the volumes using the
following command:
`# gluster volume status clients`
For example, to display the list of clients connected to
test-volume:
# gluster volume status test-volume clients
Brick : arch:/export/1
Clients connected : 2
Hostname Bytes Read BytesWritten
-------- --------- ------------
127.0.0.1:1013 776 676
127.0.0.1:1012 50440 51200
- Display the memory usage and memory pool details of the bricks using
the following command:
`# gluster volume status mem`
For example, to display the memory usage and memory pool details of
the bricks of test-volume:
Memory status for volume : test-volume
----------------------------------------------
Brick : arch:/export/1
Mallinfo
--------
Arena : 434176
Ordblks : 2
Smblks : 0
Hblks : 12
Hblkhd : 40861696
Usmblks : 0
Fsmblks : 0
Uordblks : 332416
Fordblks : 101760
Keepcost : 100400
Mempool Stats
-------------
Name HotCount ColdCount PaddedSizeof AllocCount MaxAlloc
---- -------- --------- ------------ ---------- --------
test-volume-server:fd_t 0 16384 92 57 5
test-volume-server:dentry_t 59 965 84 59 59
test-volume-server:inode_t 60 964 148 60 60
test-volume-server:rpcsvc_request_t 0 525 6372 351 2
glusterfs:struct saved_frame 0 4096 124 2 2
glusterfs:struct rpc_req 0 4096 2236 2 2
glusterfs:rpcsvc_request_t 1 524 6372 2 1
glusterfs:call_stub_t 0 1024 1220 288 1
glusterfs:call_stack_t 0 8192 2084 290 2
glusterfs:call_frame_t 0 16384 172 1728 6
- Display the inode tables of the volume using the following command:
`# gluster volume status inode`
For example, to display the inode tables of the test-volume:
# gluster volume status test-volume inode
inode tables for volume test-volume
----------------------------------------------
Brick : arch:/export/1
Active inodes:
GFID Lookups Ref IA type
---- ------- --- -------
6f3fe173-e07a-4209-abb6-484091d75499 1 9 2
370d35d7-657e-44dc-bac4-d6dd800ec3d3 1 1 2
LRU inodes:
GFID Lookups Ref IA type
---- ------- --- -------
80f98abe-cdcf-4c1d-b917-ae564cf55763 1 0 1
3a58973d-d549-4ea6-9977-9aa218f233de 1 0 1
2ce0197d-87a9-451b-9094-9baa38121155 1 0 2
- Display the open fd tables of the volume using the following
command:
`# gluster volume status fd`
For example, to display the open fd tables of the test-volume:
# gluster volume status test-volume fd
FD tables for volume test-volume
----------------------------------------------
Brick : arch:/export/1
Connection 1:
RefCount = 0 MaxFDs = 128 FirstFree = 4
FD Entry PID RefCount Flags
-------- --- -------- -----
0 26311 1 2
1 26310 3 2
2 26310 1 2
3 26311 3 2
Connection 2:
RefCount = 0 MaxFDs = 128 FirstFree = 0
No open fds
Connection 3:
RefCount = 0 MaxFDs = 128 FirstFree = 0
No open fds
- Display the pending calls of the volume using the following command:
`# gluster volume status callpool`
Each call has a call stack containing call frames.
For example, to display the pending calls of test-volume:
# gluster volume status test-volume
Pending calls for volume test-volume
----------------------------------------------
Brick : arch:/export/1
Pending calls: 2
Call Stack1
UID : 0
GID : 0
PID : 26338
Unique : 192138
Frames : 7
Frame 1
Ref Count = 1
Translator = test-volume-server
Completed = No
Frame 2
Ref Count = 0
Translator = test-volume-posix
Completed = No
Parent = test-volume-access-control
Wind From = default_fsync
Wind To = FIRST_CHILD(this)->fops->fsync
Frame 3
Ref Count = 1
Translator = test-volume-access-control
Completed = No
Parent = repl-locks
Wind From = default_fsync
Wind To = FIRST_CHILD(this)->fops->fsync
Frame 4
Ref Count = 1
Translator = test-volume-locks
Completed = No
Parent = test-volume-io-threads
Wind From = iot_fsync_wrapper
Wind To = FIRST_CHILD (this)->fops->fsync
Frame 5
Ref Count = 1
Translator = test-volume-io-threads
Completed = No
Parent = test-volume-marker
Wind From = default_fsync
Wind To = FIRST_CHILD(this)->fops->fsync
Frame 6
Ref Count = 1
Translator = test-volume-marker
Completed = No
Parent = /export/1
Wind From = io_stats_fsync
Wind To = FIRST_CHILD(this)->fops->fsync
Frame 7
Ref Count = 1
Translator = /export/1
Completed = No
Parent = test-volume-server
Wind From = server_fsync_resume
Wind To = bound_xl->fops->fsync