Difference between revisions of "ProcFS"

Revision as of 20:45, 18 March 2007

Information about currently running contexts can be found inside the /proc/virtual and /proc/virtnet directory. All information provided there is read-only, i.e. it cannot be used to change any values like other entries in /proc may do. Because it usually is world-readable you do not have to gain root access to look at this information.

Beside this information you can also control various debugging related settings using /proc/sys/vserver/debug if you have enabled debugging in your kernel configuration.

Note: The examples and descriptions are based on the 2.1.1 kernel patch. If you're using a previous version some information may not be present and/or available with a slightly different name.

Generic information

Currently there is only one file with generic information about the vserver host, that is /proc/virtual/info:

info

# cat /proc/virtual/info
VCIVersion:     0002:0002
VCISyscall:     236
VCIKernel:      03000016

VCIVersion 

Current API version of the kernel

VCISyscall 

Syscall number of the vserver syscall

VCIKernel 

Bitmask of the CONFIG_VSERVER kernel configuration options

Beside VCIKernel the information provided in this file can also be gathered using the vserver-info utility from util-vserver.

# vserver-info
Versions:
                  Kernel: 2.6.17-2-vserver-amd64
                  VS-API: 0x00020002
            util-vserver: 0.30.210; Sep 30 2006, 23:55:41
Features:
                      CC: gcc, gcc (GCC) 4.1.2 20060928 (prerelease) (Debian 4.1.1-15)
                     CXX: g++, g++ (GCC) 4.1.2 20060928 (prerelease) (Debian 4.1.1-15)
                CPPFLAGS: ''
                  CFLAGS: '-Wall -g  -O2 -std=c99 -Wall -pedantic -W -funit-at-a-time'
                CXXFLAGS: '-g -O2 -ansi -Wall -pedantic -W -fmessage-length=0 -funit-at-a-time'
              build/host: x86_64-pc-linux-gnu/x86_64-pc-linux-gnu
            Use dietlibc: yes
      Build C++ programs: yes
      Build C99 programs: yes
          Available APIs: compat,v11,fscompat,v13,net,oldproc,olduts
           ext2fs Source: e2fsprogs
   syscall(2) invocation: alternative
     vserver(2) syscall#: 236/glibc

Context specific information

info

# cat /proc/virtual/<xid>/info
ID:	1001
Info:	83c37000
Init:	0

ID 

Context ID

Info 

Memory location of the vx_info structure

Init 

Real PID of the init process

status

This file contains general status information.

# cat /proc/virtual/<xid>/status 
UseCnt:	38
Tasks:	16
Flags:	0000000002020010
BCaps:	00000000344c04ff
CCaps:	0000000000000101

UseCnt 

References to the vx_info struct

Tasks 

Number of processes (tasks) inside the context

Flags 

Capabilities and Flags

BCaps 

Capabilities and Flags

CCaps 

Capabilities and Flags

sched

This file contains information about the CPU Scheduler.

# cat /proc/virtual/<xid>/sched 
FillRate:              1,1
Interval:              4,8
TokensMin:            15
TokensMax:           125
PrioBias:              0
VaVaVoom:              0
cpu 0: 0 0 0 0 0 R- 62 15 125 1/4 1/8

FillRate 

Number of tokens filled into the bucket at each interval

Interval 

Number of jiffies between each fill interval

TokensMin 

Minimum number of tokens to be scheduled

TokensMax 

Maximum number of tokens in the bucket

PrioBias 

Priority bias

VaVaVoom 

The calculated priority bonus a guest gets

cpu X

Ticks spent in user-space

Ticks spent in kernel-space

Ticks spent on hold

Token time ??

Idle time ??

On hold (H) or running (R)

Uses IDLE time (I) or not (-)

Current number of tokens

Minimum number of tokens to be scheduled

Maximum number of tokens in the bucket

Minimum number of tokens to be scheduled (IDLE time setting)

Maximum number of tokens in the bucket (IDLE time setting)

cacct

This file contains information about Context Accounting, including socket accounting and slab allocator accounting.

# cat /proc/virtual/<xid>/cacct 
Type        recv #/bytes                   send #/bytes             fail #/bytes
UNSPEC:          0/0                     0/0                     0/0
UNIX:            0/0                     0/0                     0/0
INET:            0/0                     0/0                     0/0
INET6:           0/0                     0/0                     0/0
PACKET:          0/0                     0/0                     0/0
OTHER:           0/0                     0/0                     0/0

slab:           0        0 4294965416        0

page[0]:        0        0        0        0            0        0        0        0
page[1]:        0        0        0        0            0        0        0        0
page[2]:        0        0        0        0            0        0        0        0
page[3]:        0        0        0        0            0        0        0        0
page[4]:        0        0        0        0            0        0        0        0

cvirt

This file contains information about virtualized data, including context uptime bias, utsname settings, thread information and load average.

# cat /proc/virtual/<xid>/cvirt 
BiasUptime:	49.73
SysName:	Linux
NodeName:	XXXX.test.org
Release:	2.6.11-rc5
Version:	#12 Sun Feb 27 01:07:29 CET 2005
Machine:	i686
DomainName:	
nr_threads:	16
nr_running:	0
nr_unintr:	0
nr_onhold:	0
load_updates:	14585
loadavg:	0.00 0.00 0.00
total_forks:	272

BiasUptime 

Context uptime bias (System uptime - BiasUptime = Context uptime)

SysName 

Kernel name

NodeName 

Network node hostname

Release 

Kernel release

Version 

Kernel version

Machine 

Machine hardware name

DomainName 

Network node domainname

nr_threads 

Total number of threads

nr_running 

Number of running threads

nr_unintr 

Number of uninterruptible threads

nr_onhold 

Number of threads on hold

load_updates 

Total number of load average updates

loadavg 

Number of jobs in the run queue averaged over 1, 5, and 15 minutes

total_forks 

Total number of forks

limit

This file contains information about Resource Limits, including Context Accounting (i.e these do not appear in cacct).

# cat /proc/virtual/<xid>/limit 
Limit    current             min/max                soft/hard           hits
PROC:          2               2/       2             -1/      -1            0
VM:         4024            4024/    4024             -1/      -1            0
VML:           0               0/       0             -1/      -1            0
RSS:          50              50/      50             -1/      -1            0
ANON:         33              33/      33             -1/      -1            0
FILES:        19              19/      19             -1/      -1            0
OFD:           5               5/       5             -1/      -1            0
LOCKS:         0               0/       0             -1/      -1            0
SOCK:          2               2/       2             -1/      -1            0
MSGQ:          0               0/       0             -1/      -1            0
SHM:           0               0/       0             -1/      -1            0
SEMA:          0               0/       0             -1/      -1            0
SEMS:          0               0/       0             -1/      -1            0
DENT:       2315            2315/    2315             -1/      -1            0

Limit 

Limit name/identifier

current 

Current value

min 

Minimum value since the last reset

max 

Maximum value since the last reset

soft 

Soft limit

hard 

hard limit

hits 

Total amount of current reaching hard

Debugging Control

The /proc/sys/vserver/debug directory is only present if you have enabled CONFIG_VSERVER_DEBUG during kernel compilation.

To enable debugging you can use a command similar to the following to enable debugging. Please see Kernel Debugging for more information.

# echo 255 >/proc/sys/vserver/debug_switch