diff options
Diffstat (limited to 'Documentation/filesystems')
-rw-r--r-- | Documentation/filesystems/ncpfs.txt | 6 | ||||
-rw-r--r-- | Documentation/filesystems/nfs41-server.txt | 54 | ||||
-rw-r--r-- | Documentation/filesystems/nfsroot.txt | 2 | ||||
-rw-r--r-- | Documentation/filesystems/proc.txt | 27 |
4 files changed, 80 insertions, 9 deletions
diff --git a/Documentation/filesystems/ncpfs.txt b/Documentation/filesystems/ncpfs.txt index f12c30c93f2..5af164f4b37 100644 --- a/Documentation/filesystems/ncpfs.txt +++ b/Documentation/filesystems/ncpfs.txt @@ -7,6 +7,6 @@ ftp.gwdg.de/pub/linux/misc/ncpfs, but sunsite and its many mirrors will have it as well. Related products are linware and mars_nwe, which will give Linux partial -NetWare server functionality. Linware's home site is -klokan.sh.cvut.cz/pub/linux/linware; mars_nwe can be found on -ftp.gwdg.de/pub/linux/misc/ncpfs. +NetWare server functionality. + +mars_nwe can be found on ftp.gwdg.de/pub/linux/misc/ncpfs. diff --git a/Documentation/filesystems/nfs41-server.txt b/Documentation/filesystems/nfs41-server.txt index 05d81cbcb2e..5920fe26e6f 100644 --- a/Documentation/filesystems/nfs41-server.txt +++ b/Documentation/filesystems/nfs41-server.txt @@ -11,6 +11,11 @@ the /proc/fs/nfsd/versions control file. Note that to write this control file, the nfsd service must be taken down. Use your user-mode nfs-utils to set this up; see rpc.nfsd(8) +(Warning: older servers will interpret "+4.1" and "-4.1" as "+4" and +"-4", respectively. Therefore, code meant to work on both new and old +kernels must turn 4.1 on or off *before* turning support for version 4 +on or off; rpc.nfsd does this correctly.) + The NFSv4 minorversion 1 (NFSv4.1) implementation in nfsd is based on the latest NFSv4.1 Internet Draft: http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-29 @@ -25,6 +30,49 @@ are still under development out of tree. See http://wiki.linux-nfs.org/wiki/index.php/PNFS_prototype_design for more information. +The current implementation is intended for developers only: while it +does support ordinary file operations on clients we have tested against +(including the linux client), it is incomplete in ways which may limit +features unexpectedly, cause known bugs in rare cases, or cause +interoperability problems with future clients. Known issues: + + - gss support is questionable: currently mounts with kerberos + from a linux client are possible, but we aren't really + conformant with the spec (for example, we don't use kerberos + on the backchannel correctly). + - no trunking support: no clients currently take advantage of + trunking, but this is a mandatory failure, and its use is + recommended to clients in a number of places. (E.g. to ensure + timely renewal in case an existing connection's retry timeouts + have gotten too long; see section 8.3 of the draft.) + Therefore, lack of this feature may cause future clients to + fail. + - Incomplete backchannel support: incomplete backchannel gss + support and no support for BACKCHANNEL_CTL mean that + callbacks (hence delegations and layouts) may not be + available and clients confused by the incomplete + implementation may fail. + - Server reboot recovery is unsupported; if the server reboots, + clients may fail. + - We do not support SSV, which provides security for shared + client-server state (thus preventing unauthorized tampering + with locks and opens, for example). It is mandatory for + servers to support this, though no clients use it yet. + - Mandatory operations which we do not support, such as + DESTROY_CLIENTID, FREE_STATEID, SECINFO_NO_NAME, and + TEST_STATEID, are not currently used by clients, but will be + (and the spec recommends their uses in common cases), and + clients should not be expected to know how to recover from the + case where they are not supported. This will eventually cause + interoperability failures. + +In addition, some limitations are inherited from the current NFSv4 +implementation: + + - Incomplete delegation enforcement: if a file is renamed or + unlinked, a client holding a delegation may continue to + indefinitely allow opens of the file under the old name. + The table below, taken from the NFSv4.1 document, lists the operations that are mandatory to implement (REQ), optional (OPT), and NFSv4.0 operations that are required not to implement (MNI) @@ -142,6 +190,12 @@ NS*| CB_WANTS_CANCELLED | OPT | FDELG, | Section 20.10 | Implementation notes: +DELEGPURGE: +* mandatory only for servers that support CLAIM_DELEGATE_PREV and/or + CLAIM_DELEG_PREV_FH (which allows clients to keep delegations that + persist across client reboots). Thus we need not implement this for + now. + EXCHANGE_ID: * only SP4_NONE state protection supported * implementation ids are ignored diff --git a/Documentation/filesystems/nfsroot.txt b/Documentation/filesystems/nfsroot.txt index 68baddf3c3e..3ba0b945aaf 100644 --- a/Documentation/filesystems/nfsroot.txt +++ b/Documentation/filesystems/nfsroot.txt @@ -105,7 +105,7 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf> the client address and this parameter is NOT empty only replies from the specified server are accepted. - Only required for for NFS root. That is autoconfiguration + Only required for NFS root. That is autoconfiguration will not be triggered if it is missing and NFS root is not in operation. diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index ffead13f944..b5aee7838a0 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -176,6 +176,7 @@ read the file /proc/PID/status: CapBnd: ffffffffffffffff voluntary_ctxt_switches: 0 nonvoluntary_ctxt_switches: 1 + Stack usage: 12 kB This shows you nearly the same information you would get if you viewed it with the ps command. In fact, ps uses the proc file system to obtain its @@ -229,6 +230,7 @@ Table 1-2: Contents of the statm files (as of 2.6.30-rc7) Mems_allowed_list Same as previous, but in "list format" voluntary_ctxt_switches number of voluntary context switches nonvoluntary_ctxt_switches number of non voluntary context switches + Stack usage: stack usage high water mark (round up to page size) .............................................................................. Table 1-3: Contents of the statm files (as of 2.6.8-rc3) @@ -307,7 +309,7 @@ address perms offset dev inode pathname 08049000-0804a000 rw-p 00001000 03:00 8312 /opt/test 0804a000-0806b000 rw-p 00000000 00:00 0 [heap] a7cb1000-a7cb2000 ---p 00000000 00:00 0 -a7cb2000-a7eb2000 rw-p 00000000 00:00 0 +a7cb2000-a7eb2000 rw-p 00000000 00:00 0 [threadstack:001ff4b4] a7eb2000-a7eb3000 ---p 00000000 00:00 0 a7eb3000-a7ed5000 rw-p 00000000 00:00 0 a7ed5000-a8008000 r-xp 00000000 03:00 4222 /lib/libc.so.6 @@ -343,6 +345,7 @@ is not associated with a file: [stack] = the stack of the main process [vdso] = the "virtual dynamic shared object", the kernel system call handler + [threadstack:xxxxxxxx] = the stack of the thread, xxxxxxxx is the stack size or if empty, the mapping is anonymous. @@ -375,6 +378,19 @@ of memory currently marked as referenced or accessed. This file is only present if the CONFIG_MMU kernel configuration option is enabled. +The /proc/PID/clear_refs is used to reset the PG_Referenced and ACCESSED/YOUNG +bits on both physical and virtual pages associated with a process. +To clear the bits for all the pages associated with the process + > echo 1 > /proc/PID/clear_refs + +To clear the bits for the anonymous pages associated with the process + > echo 2 > /proc/PID/clear_refs + +To clear the bits for the file mapped pages associated with the process + > echo 3 > /proc/PID/clear_refs +Any other value written to /proc/PID/clear_refs will have no effect. + + 1.2 Kernel data --------------- @@ -1032,9 +1048,9 @@ Various pieces of information about kernel activity are available in the since the system first booted. For a quick look, simply cat the file: > cat /proc/stat - cpu 2255 34 2290 22625563 6290 127 456 0 - cpu0 1132 34 1441 11311718 3675 127 438 0 - cpu1 1123 0 849 11313845 2614 0 18 0 + cpu 2255 34 2290 22625563 6290 127 456 0 0 + cpu0 1132 34 1441 11311718 3675 127 438 0 0 + cpu1 1123 0 849 11313845 2614 0 18 0 0 intr 114930548 113199788 3 0 5 263 0 4 [... lots more numbers ...] ctxt 1990473 btime 1062191376 @@ -1056,6 +1072,7 @@ second). The meanings of the columns are as follows, from left to right: - irq: servicing interrupts - softirq: servicing softirqs - steal: involuntary wait +- guest: running a guest The "intr" line gives counts of interrupts serviced since boot time, for each of the possible system interrupts. The first column is the total of all @@ -1191,7 +1208,7 @@ The following heuristics are then applied: * if the task was reniced, its score doubles * superuser or direct hardware access tasks (CAP_SYS_ADMIN, CAP_SYS_RESOURCE or CAP_SYS_RAWIO) have their score divided by 4 - * if oom condition happened in one cpuset and checked task does not belong + * if oom condition happened in one cpuset and checked process does not belong to it, its score is divided by 8 * the resulting score is multiplied by two to the power of oom_adj, i.e. points <<= oom_adj when it is positive and |