# Brief Data

This format does NOT include data for any individual devices such as cpu, disk, network, nfs, lustre, process, slabs or tcp. If you do select any one of them collectl will force --verbose format.

### Buddy (Memory Fragmentation) Data, collectl -sB

The smaller the value the more accuracy as follows:

- 0-9 are represented by the digits 0 through 9
- 10-99 by the letters a through i
- 100-999 by the letters j through r
- >1000 by powers of 10, using s through z

Remember, the whole purpose of monitoring fragments in brief mode is to identify trends, particularly when there are a small number of them.

    #<---Memory-->
    #   Fragments
      smkj9576040

### CPU Data, collectl -sc

    #<--------CPU-------->
    #cpu sys inter  ctxsw

cpu | Percent of time the cpu was busy during the current interval averaged across all CPUs and is actually the total percentage of time the CPU in one of the following: system, user, nice, irq, soft-irq and steal. Note that this does NOT include time spend in I/O wait.
sys | Percentage of time the cpu was executing in system mode during the current interval. This includes all those modes as above except user and nice to to determine the amount of time spent as a user you need to subtract these from the total cpu field.
inter | Total number of interrupts/sec.
ctxsw | Total number of context switches/sec.

### Disk, collectl -sd

If you specify filtering with --dskfilt, the disks that match the pattern(s) will either be included or excluded from the the summary data. However, the data will still be collected so if recorded to a file can later be viewed.

    #<---------------Disks---------------->
    #KBRead  Reads  Size KBWrit Writes Size

KBRead | KB read/sec
Reads | Number of reads/sec
Size | Average read size in KB. This field only included if --dskopts i or --iosize specified
KBWrite | KB written/sec
Writes | Number of writes/sec
Size | Average write size in KB. This field only included if --dskopts i or --iosize specified

### Infiniband, collectl -sx

    #<---------------InfiniBand--------------->
    #  KBIn  PktIn Size  KBOut PktOut Size Errs

KBIn | KB received/sec.
PckIn | Packets received/sec.
Size | Average incoming packet size in KB. This field is only included if --xopts i or --iosize included
KBOut | KB sent/sec.
PktOut | Packets sent/sec.
Size | Average outgoing packet size in KB. This field is only included if --xopts i or --iosize included
Errs | Count of current errors. Since these are typically infrequent, it is felt that reporting them as a rate would result in either not seeing them OR round-off hiding their values.

### Inodes/Filesystem, collectl -si

    #<----Files--->
    #Handle Inodes
       5100 116110

Handles | Number of allocated file handles
Inodes | Number of inodes in use

### Lustre

Lustre data actually falls into one of 3 categories - client, mds and oss. Collectl determines the type of system it is running on (a system can have multiple personalities) and reports on all it finds, unless specifically selected via -L.

Lustre Client, collectl -sl

    #<-------------Lustre Client------------->
    # KBRead  Reads Size  KBWrite Writes Size

KBRead | KB/sec delivered to the client.
Reads | Reads/sec delivered to the client,
Size | Average read size in KB. This field only included if --iosize specified
not necessarily from the lustre storage servers.
KBWrite | KB Writes/sec delivered to the storage servers.
Writes | Writes/sec delivered to the storage servers.
Size | Average write size in KB. This field only included if --iosize specified

The following format of lustre client data is selected by including -OR and adds readahead statistics to the previous six, noting the Size fields are dependent on --iosize being specificed.

    #<--------------------Lustre Client-------------------->
    # KBRead  Reads Size  KBWrite Writes Size   Hits Misses

KBRead | KB/sec delivered to the client.
Reads | Reads/sec delivered to the client, not necessarily from the lustre storage servers.
Size | Average read size in KB.
KBWrite | KB Writes/sec delivered to the storage servers.
Writes | Writes/sec delivered to the storage servers.
Size | Average write size in KB.
Hits | Number of reads/sec from the lustre prefetch cache.
Misses | Number of misses/sec from the prefetch cache which must then be satisfied by reading from the storage servers.

Lustre MDS (Meta-Data Server)
The first format is for lustre versions 1.6.5 and beyond while the second format is for earlier releases

    #<--------Lustre MDS-------->
    #Gattr+ Sattr+   Sync  Unlnk

    #<--------Lustre MDS-------->
    #Gattr+ Sattr+   Sync  Reint

Gattr+ | Total number of all getattr operations/sec. See Getattr, GttrLck and Gxattr in the verbose data section
Sattr+ | Total number of all getattr operations/sec. See Setattr and Sxattr in the verbose data section
Sync | Number of syncs/sec
Unlnk | Number of file deletes/sec
Reint | Number of reints/sec which include unlinks and setattrs. Since older version did not break out setattrs, they are not included in Sattr+.

Lustre OSS (Object Storage Server), collectl -sc

    #<--------------Lustre OST-------------->
    # KBRead  Reads Size  KBWrit Writes Size

KBRead | KB/sec read
Reads | Reads/sec
Size | Average read size in KB. This field only included if --iosize specified
KBWrite | KB/sec written
Writes | Writes/sec
Size | Average write size in KB. This field only included if --iosize specified

### Memory, collectl -sm

    #<-----------Memory---------->
    #free buff cach inac slab  map

free | Total free memory, which unfortunately is NOT the difference between total memory and the following amounts allocated to used memory.
buff | Memory used as system buffers.
cach | This is also commonly known as the file system buffer cache as buffered I/O uses this memory to cache the data.
inac | Inactive memory.
slab | Total memory allocated to slabs.
map | Total mapped memory, which include AnonPages.

Note
If you include --memopts R, these values wil be displayed as changes/sec between intervals rather than absolute values. This switch will also honor -on in that the values will not be normalized to a rate but rather displayed as changes in size per interval.

### Network, collectl -sn

If you specify filtering with --netfilt, the names that match the pattern(s) will either be included or excluded from the the summary data. However, the data will still be collected so if recorded to a file can later be viewed.

Also be sure to keep in mind that like all other data, network counters are always normalized to /sec rates. This means that something like errors, which themselves might be really small, could be reported as 0 if less than 1/2 the sampling interval. To see unnormalized values use -on.

    #<------------------Network------------------>
    #  KBIn  PktIn Size  KBOut  PktOut Size Error

KBIn | KB received/sec over all real network interfaces and therefore excludes 'lo' and 'sit'.
PktIn | Packets received/sec over all real network interfaces.
Size | Average incoming packet size in bytes. This field is only included if --netopts i or --iosize specified
KBOut | KB sent/sec over all real network interfaces.
PktOut | Packets sent/sec over all real network interfaces.
Size | Average outgoing packet size in bytes. This field is only included if --netopts i or --iosize specified
Error | Total incoming/outgoing errors/sec. To see individual error counts, use --verbose. This field is only included if --netopts e specified

### NFS, collectl -sf

As of version 3.2.1 collectl now collects all types of nfs data, both clients and servers as well as versions 2, 3 and 4. In brief format it therefore reports summaried data across all nfs types as shown below. If --nfsfilt was included in the command to limit the types of data reported, those values will be included in the header line as a reminder as shown in the second form to the right, in which case only V3 server and V4 client data are being summarized.

    #<------NFS Totals------>            #<------NFS [s3,c4]----->
    # Reads Writes Meta Comm             # Reads Writes Meta Comm

Reads | Total nfs reads/sec.
Writes | Total nfs writes/sec.
Meta | Total nfs meta data calls/sec, where meta data is considered to be any of: lookup, access, getattr, setattr, readdir and readdirplus, noting that not all types of nfs version report all as V3 clients/servers do.
Comm | Total nfs commits/sec.

### Slabs, collectl -sy

    #<----slab---->
    # Alloc   Bytes

Alloc | Total Number of slabs allocated
Bytes | Total Number of bytes allocated as slabs

### Sockets, collectl -ss

    #<------Sockets----->
    #  Tcp  Udp  Raw Frag

Tcp | Total TCP sockets currently in use.
Udp | Total UDP sockets currently in use.
Raw | Total RAW sockets currently in use.
Frag | Total number of IP fragments queues currently in use.

### TCP, collectl -st

The TCP data collected and actually depends on the value of --tcpfilt, which by default is set to itcu, which stands for IP, Tcp, Udp and ICMP. A 5th filter T will result in Tcp Extended values being reported.

    #<----------TCP---------->
    #  IP  Tcp  Udp Icmp TcpX
        0    0    0    0    0

IPSummary of a number of IP errors from /prod/net/snmp: InHdrErrors+InAddrErrors+InUnknownProtos+InDiscards+OutDiscards+ReasmFails+FragFails
TcpSummary of a number of Tcp errors from /prod/net/snmp: AttemptFails+InErrs
UdpSummary of a number of Udp errors, from /prod/net/snmp: NoPorts+InErrors
IcmpSummary of a number of Icmp errors, from /prod/net/snmp: InErrors+InDestUnreachs+OutErrors
TcpXSummary of a number of Txp Extended errors, from /prod/net/snmp: TcpLoss+TCPFastRetrans

updated September 29, 2011