proc.txt

来自「Linux Kernel 2.6.9 for OMAP1710」· 文本 代码 · 共 1,564 行 · 第 1/5 页

  > echo 1 > /proc/irq/prof_cpu_mask

This means that only the first CPU will handle the IRQ, but you can also echo 5
wich means that only the first and fourth CPU can handle the IRQ.

The way IRQs are routed is handled by the IO-APIC, and it's Round Robin
between all the CPUs which are allowed to handle it. As usual the kernel has
more info than you and does a better job than you, so the defaults are the
best choice for almost everyone.

There are  three  more  important subdirectories in /proc: net, scsi, and sys.
The general  rule  is  that  the  contents,  or  even  the  existence of these
directories, depend  on your kernel configuration. If SCSI is not enabled, the
directory scsi  may  not  exist. The same is true with the net, which is there
only when networking support is present in the running kernel.

The slabinfo  file  gives  information  about  memory usage at the slab level.
Linux uses  slab  pools for memory management above page level in version 2.2.
Commonly used  objects  have  their  own  slab  pool (such as network buffers,
directory cache, and so on).

..............................................................................

> cat /proc/buddyinfo

Node 0, zone      DMA      0      4      5      4      4      3 ...
Node 0, zone   Normal      1      0      0      1    101      8 ...
Node 0, zone  HighMem      2      0      0      1      1      0 ...

Memory fragmentation is a problem under some workloads, and buddyinfo is a 
useful tool for helping diagnose these problems.  Buddyinfo will give you a 
clue as to how big an area you can safely allocate, or why a previous
allocation failed.

Each column represents the number of pages of a certain order which are 
available.  In this case, there are 0 chunks of 2^0*PAGE_SIZE available in 
ZONE_DMA, 4 chunks of 2^1*PAGE_SIZE in ZONE_DMA, 101 chunks of 2^4*PAGE_SIZE 
available in ZONE_NORMAL, etc... 


1.3 IDE devices in /proc/ide
----------------------------

The subdirectory /proc/ide contains information about all IDE devices of which
the kernel  is  aware.  There is one subdirectory for each IDE controller, the
file drivers  and a link for each IDE device, pointing to the device directory
in the controller specific subtree.

The file  drivers  contains general information about the drivers used for the
IDE devices:

  > cat /proc/ide/drivers 
  ide-cdrom version 4.53 
  ide-disk version 1.08 

..............................................................................

meminfo:

Provides information about distribution and utilization of memory.  This
varies by architecture and compile options.  The following is from a
16GB PIII, which has highmem enabled.  You may not have all of these fields.

> cat /proc/meminfo


MemTotal:     16344972 kB
MemFree:      13634064 kB
Buffers:          3656 kB
Cached:        1195708 kB
SwapCached:          0 kB
Active:         891636 kB
Inactive:      1077224 kB
HighTotal:    15597528 kB
HighFree:     13629632 kB
LowTotal:       747444 kB
LowFree:          4432 kB
SwapTotal:           0 kB
SwapFree:            0 kB
Dirty:             968 kB
Writeback:           0 kB
Mapped:         280372 kB
Slab:           684068 kB
Committed_AS:  1576424 kB
PageTables:      24448 kB
ReverseMaps:   1080904
VmallocTotal:   112216 kB
VmallocUsed:       428 kB
VmallocChunk:   111088 kB

    MemTotal: Total usable ram (i.e. physical ram minus a few reserved
              bits and the kernel binary code)
     MemFree: The sum of LowFree+HighFree
     Buffers: Relatively temporary storage for raw disk blocks
              shouldn't get tremendously large (20MB or so)
      Cached: in-memory cache for files read from the disk (the
              pagecache).  Doesn't include SwapCached
  SwapCached: Memory that once was swapped out, is swapped back in but
              still also is in the swapfile (if memory is needed it
              doesn't need to be swapped out AGAIN because it is already
              in the swapfile. This saves I/O)
      Active: Memory that has been used more recently and usually not
              reclaimed unless absolutely necessary.
    Inactive: Memory which has been less recently used.  It is more
              eligible to be reclaimed for other purposes
   HighTotal:
    HighFree: Highmem is all memory above ~860MB of physical memory
              Highmem areas are for use by userspace programs, or
              for the pagecache.  The kernel must use tricks to access
              this memory, making it slower to access than lowmem.
    LowTotal:
     LowFree: Lowmem is memory which can be used for everything that
              highmem can be used for, but it is also availble for the
              kernel's use for its own data structures.  Among many
              other things, it is where everything from the Slab is
              allocated.  Bad things happen when you're out of lowmem.
   SwapTotal: total amount of swap space available
    SwapFree: Memory which has been evicted from RAM, and is temporarily
              on the disk
       Dirty: Memory which is waiting to get written back to the disk
   Writeback: Memory which is actively being written back to the disk
      Mapped: files which have been mmaped, such as libraries
              Slab: in-kernel data structures cache
Committed_AS: An estimate of how much RAM you would need to make a
              99.99% guarantee that there never is OOM (out of memory)
              for this workload. Normally the kernel will overcommit
              memory. That means, say you do a 1GB malloc, nothing
              happens, really. Only when you start USING that malloc
              memory you will get real memory on demand, and just as
              much as you use. So you sort of take a mortgage and hope
              the bank doesn't go bust. Other cases might include when
              you mmap a file that's shared only when you write to it
              and you get a private copy of that data. While it normally
              is shared between processes. The Committed_AS is a
              guesstimate of how much RAM/swap you would need
              worst-case.
  PageTables: amount of memory dedicated to the lowest level of page
              tables.
 ReverseMaps: number of reverse mappings performed
VmallocTotal: total size of vmalloc memory area
 VmallocUsed: amount of vmalloc area which is used
VmallocChunk: largest contigious block of vmalloc area which is free

More detailed  information  can  be  found  in  the  controller  specific
subdirectories. These  are  named  ide0,  ide1  and  so  on.  Each  of  these
directories contains the files shown in table 1-4.


Table 1-4: IDE controller info in  /proc/ide/ide? 
..............................................................................
 File    Content                                 
 channel IDE channel (0 or 1)                    
 config  Configuration (only for PCI/IDE bridge) 
 mate    Mate name                               
 model   Type/Chipset of IDE controller          
..............................................................................

Each device  connected  to  a  controller  has  a separate subdirectory in the
controllers directory.  The  files  listed in table 1-5 are contained in these
directories.


Table 1-5: IDE device information 
..............................................................................
 File             Content                                    
 cache            The cache                                  
 capacity         Capacity of the medium (in 512Byte blocks) 
 driver           driver and version                         
 geometry         physical and logical geometry              
 identify         device identify block                      
 media            media type                                 
 model            device identifier                          
 settings         device setup                               
 smart_thresholds IDE disk management thresholds             
 smart_values     IDE disk management values                 
..............................................................................

The most  interesting  file is settings. This file contains a nice overview of
the drive parameters:

  # cat /proc/ide/ide0/hda/settings 
  name                    value           min             max             mode 
  ----                    -----           ---             ---             ---- 
  bios_cyl                526             0               65535           rw 
  bios_head               255             0               255             rw 
  bios_sect               63              0               63              rw 
  breada_readahead        4               0               127             rw 
  bswap                   0               0               1               r 
  file_readahead          72              0               2097151         rw 
  io_32bit                0               0               3               rw 
  keepsettings            0               0               1               rw 
  max_kb_per_request      122             1               127             rw 
  multcount               0               0               8               rw 
  nice1                   1               0               1               rw 
  nowerr                  0               0               1               rw 
  pio_mode                write-only      0               255             w 
  slow                    0               0               1               rw 
  unmaskirq               0               0               1               rw 
  using_dma               0               0               1               rw 


1.4 Networking info in /proc/net
--------------------------------

The subdirectory  /proc/net  follows  the  usual  pattern. Table 1-6 shows the
additional values  you  get  for  IP  version 6 if you configure the kernel to
support this. Table 1-7 lists the files and their meaning.


Table 1-6: IPv6 info in /proc/net 
..............................................................................
 File       Content                                               
 udp6       UDP sockets (IPv6)                                    
 tcp6       TCP sockets (IPv6)                                    
 raw6       Raw device statistics (IPv6)                          
 igmp6      IP multicast addresses, which this host joined (IPv6) 
 if_inet6   List of IPv6 interface addresses                      
 ipv6_route Kernel routing table for IPv6                         
 rt6_stats  Global IPv6 routing tables statistics                 
 sockstat6  Socket statistics (IPv6)                              
 snmp6      Snmp data (IPv6)                                      
..............................................................................


Table 1-7: Network info in /proc/net 
..............................................................................
 File          Content                                                         
 arp           Kernel  ARP table                                               
 dev           network devices with statistics                                 
 dev_mcast     the Layer2 multicast groups a device is listening too
               (interface index, label, number of references, number of bound
               addresses). 
 dev_stat      network device status                                           
 ip_fwchains   Firewall chain linkage                                          
 ip_fwnames    Firewall chain names                                            
 ip_masq       Directory containing the masquerading tables                    
 ip_masquerade Major masquerading table                                        
 netstat       Network statistics                                              
 raw           raw device statistics                                           
 route         Kernel routing table                                            
 rpc           Directory containing rpc info                                   
 rt_cache      Routing cache                                                   
 snmp          SNMP data                                                       
 sockstat      Socket statistics                                               
 tcp           TCP  sockets                                                    
 tr_rif        Token ring RIF routing table                                    
 udp           UDP sockets                                                     
 unix          UNIX domain sockets                                             
 wireless      Wireless interface data (Wavelan etc)                           
 igmp          IP multicast addresses, which this host joined                  
 psched        Global packet scheduler parameters.                             
 netlink       List of PF_NETLINK sockets                                      
 ip_mr_vifs    List of multicast virtual interfaces                            
 ip_mr_cache   List of multicast routing cache                                 
..............................................................................

You can  use  this  information  to see which network devices are available in
your system and how much traffic was routed over those devices:

  > cat /proc/net/dev 
  Inter-|Receive                                                   |[... 
   face |bytes    packets errs drop fifo frame compressed multicast|[... 
      lo:  908188   5596     0    0    0     0          0         0 [...         
    ppp0:15475140  20721   410    0    0   410          0         0 [...  
    eth0:  614530   7085     0    0    0     0          0         1 [... 
   
  ...] Transmit 
  ...] bytes    packets errs drop fifo colls carrier compressed 
  ...]  908188     5596    0    0    0     0       0          0 
  ...] 1375103    17405    0    0    0     0       0          0 
  ...] 1703981     5535    0    0    0     3       0          0 

In addition, each Channel Bond interface has it's own directory.  For
example, the bond0 device will have a directory called /proc/net/bond0/.
It will contain information that is specific to that bond, such as the
current slaves of the bond, the link status of the slaves, and how
many times the slaves link has failed.

1.5 SCSI info
-------------

If you  have  a  SCSI  host adapter in your system, you'll find a subdirectory
named after  the driver for this adapter in /proc/scsi. You'll also see a list
of all recognized SCSI devices in /proc/scsi:

  >cat /proc/scsi/scsi 
  Attached devices: 
  Host: scsi0 Channel: 00 Id: 00 Lun: 00 
    Vendor: IBM      Model: DGHS09U          Rev: 03E0 
    Type:   Direct-Access                    ANSI SCSI revision: 03 
  Host: scsi0 Channel: 00 Id: 06 Lun: 00 
    Vendor: PIONEER  Model: CD-ROM DR-U06S   Rev: 1.04 
    Type:   CD-ROM                           ANSI SCSI revision: 02 


The directory  named  after  the driver has one file for each adapter found in
the system.  These  files  contain information about the controller, including
the used  IRQ  and  the  IO  address range. The amount of information shown is
dependent on  the adapter you use. The example shows the output for an Adaptec
AHA-2940 SCSI adapter:

  > cat /proc/scsi/aic7xxx/0 
   
  Adaptec AIC7xxx driver version: 5.1.19/3.2.4 
  Compile Options: 
    TCQ Enabled By Default : Disabled 
    AIC7XXX_PROC_STATS     : Disabled 
    AIC7XXX_RESET_DELAY    : 5 
  Adapter Configuration: 
             SCSI Adapter: Adaptec AHA-294X Ultra SCSI host adapter 
                             Ultra Wide Controller 
      PCI MMAPed I/O Base: 0xeb001000 
   Adapter SEEPROM Config: SEEPROM found and used.