From a19c44b83b96fefad131ef324c3eb2916e8c604c Mon Sep 17 00:00:00 2001 From: rsc Date: Mon, 3 Jan 2005 06:41:38 +0000 Subject: Add mkfile to keep indices up to date. Remove man pages for things we don't provide. --- man/man8/ventiaux.8 | 504 ---------------------------------------------------- 1 file changed, 504 deletions(-) delete mode 100644 man/man8/ventiaux.8 (limited to 'man/man8/ventiaux.8') diff --git a/man/man8/ventiaux.8 b/man/man8/ventiaux.8 deleted file mode 100644 index fb6d8522..00000000 --- a/man/man8/ventiaux.8 +++ /dev/null @@ -1,504 +0,0 @@ -.TH VENTIAUX 8 -.SH NAME -buildindex, -checkarenas, -checkindex, -conf, -copy, -fmtarenas, -fmtindex, -fmtisect, -rdarena, -rdarenablocks, -read, -wrarenablocks, -write \- Venti maintenance and debugging commands -.SH SYNOPSIS -.B venti/buildindex -[ -.B -B -.I blockcachesize -] -[ -.B -Z -] -.I venti.config -.I tmp -.PP -.B venti/checkarenas -[ -.B -afv -] -.I file -.PP -.B venti/checkindex -[ -.B -f -] -[ -.B -B -.I blockcachesize -] -.I venti.config -.I tmp -.PP -.B venti/conf -[ -.B -w -] -.I partition -[ -.I configfile -] -.PP -.B venti/copy -[ -.B -f -] -.I src -.I dst -.I score -[ -.I type -] -.PP -.B venti/fmtarenas -[ -.B -Z -] -[ -.B -a -.I arenasize -] -[ -.B -b -.I blocksize -] -.I name -.I file -.PP -.B venti/fmtindex -[ -.B -a -] -.I venti.config -.PP -.B venti/fmtisect -[ -.B -Z -] -[ -.B -b -.I blocksize -] -.I name -.I file -.PP -.B venti/rdarena -[ -.B -v -] -.I arenapart -.I arenaname -.PP -.B venti/read -[ -.B -h -.I host -] -.I score -[ -.I type -] -.PP -.B venti/wrarena -[ -.B -o -.I fileoffset -] -[ -.B -h -.I host -] -.I arenafile -[ -.I clumpoffset -] -.PP -.B venti/write -[ -.B -h -.I host -] -[ -.B -t -.I type -] -[ -.B -z -] -.SH DESCRIPTION -These commands aid in the setup, maintenance, and debugging of -Venti servers. -See -.IR venti (8) -and -.IR venti.conf (6) -for an overview of the data structures stored by Venti. -.PP -Note that the units for the various sizes in the following -commands can be specified by appending -.LR k , -.LR m , -or -.LR g -to indicate kilobytes, megabytes, or gigabytes respectively. -.PP -.I Buildindex -populates the index for the Venti system described in -.IR venti.config . -The index must have previously been formatted using -.IR fmtindex . -This command is typically used to build a new index for a Venti -system when the old index becomes too small, or to rebuild -an index after media failure. -Small errors in an index can usually be fixed with -.IR checkindex . -.PP -The -.I tmp -file, usually a disk partition, must be large enough to store a copy of the index. -This temporary space is used to perform a merge sort of index entries -generated by reading the arenas. -.PP -Options to -.I buildindex -are: -.TP -.BI -B " blockcachesize -The amount of memory, in bytes, to use for caching raw disk accesses while running -.IR buildindex . -(This is not a property of the created index.) -The default is 8k. -.TP -.B -Z -Do not zero the index. -This option should only be used when it is known that the index was already zeroed. -.PD -.PP -.I Checkarenas -examines the Venti arenas contained in the given -.IR file . -The program detects various error conditions, and optionally attempts -to fix any errors that are found. -.PP -Options to -.I checkarenas -are: -.TP -.B -a -For each arena, scan the entire data section. -If this option is omitted, only the end section of -the arena is examined. -.TP -.B -f -Attempt to fix any errors that are found. -.TP -.B -v -Increase the verbosity of output. -.PD -.PP -.I Checkindex -examines the Venti index described in -.IR venti.config . -The program detects various error conditions including: -blocks that are not indexed, index entries for blocks that do not exist, -and duplicate index entries. -If requested, an attempt can be made to fix errors that are found. -.PP -The -.I tmp -file, usually a disk partition, must be large enough to store a copy of the index. -This temporary space is used to perform a merge sort of index entries -generated by reading the arenas. -.PP -Options to -.I checkindex -are: -.TP -.BI -B " blockcachesize -The amount of memory, in bytes, to use for caching raw disk accesses while running -.IR checkindex . -The default is 8k. -.TP -.B -f -Attempt to fix any errors that are found. -.PD -.PP -.I Fmtarenas -formats the given -.IR file , -typically a disk partition, into a number of -Venti -arenas. -The arenas are given names of the form -.IR name%d , -where -.I %d -is replaced with a sequential number starting at 0. -.PP -Options to -.I fmtarenas -are: -.TP -.BI -a " arenasize -The arenas are of -.I arenasize -bytes. The default is 512 megabytes, which was selected to provide a balance -between the number of arenas and the ability to copy an arena to external -media such as recordable CDs and tapes. -.TP -.BI -b " blocksize -The size, in bytes, for read and write operations to the file. -The size is recorded in the file, and is used by applications that access the arenas. -The default is 8k. -.TP -.B -Z -Do not zero the data sections of the arenas. -Using this option reduces the formatting time -but should only be used when it is known that the file was already zeroed. -.PD -.I Fmtindex -takes the -.IR venti.conf (6) -file -.I venti.config -and initializes the index sections to form a usable index structure. -The arena files and index sections must have previously been formatted -using -.I fmtarenas -and -.I fmtisect -respectively. -.PP -The function of a Venti index is to map a SHA1 fingerprint to a location -in the data section of one of the arenas. The index is composed of -blocks, each of which contains the mapping for a fixed range of possible -fingerprint values. -.I Fmtindex -determines the mapping between SHA1 values and the blocks -of the collection of index sections. Once this mapping has been determined, -it cannot be changed without rebuilding the index. -The basic assumption in the current implementation is that the index -structure is sufficiently empty that individual blocks of the index will rarely -overflow. The total size of the index should be about 2% to 10% of -the total size of the arenas, but the exact depends both the index block size -and the compressed size of block stored to Venti. -.PP -.I Fmtindex -also computes a mapping between a linear address space and -the data section of the collection of arenas. The -.B -a -option can be used to add additional arenas to an index. -To use this feature, -add the new arenas to -.I venti.config -after the existing arenas and then run -.I fmtindex -.BR -a . -.PP -A copy of the above mappings is stored in the header for each of the index sections. -These copies enable -.I buildindex -to restore a single index section without rebuilding the entire index. -.PP -.I Fmtisect -formats the given -.IR file , -typically a disk partition, as a Venti index section with the specified -.IR name . -One or more formatted index sections are combined into a Venti -index using -.IR fmtindex . -Each of the index sections within an index must have a unique name. -.PP -Options to -.I fmtisect -are: -.TP -.BI -b " blocksize -The size, in bytes, for read and write operations to the file. -All the index sections within a index must have the same block size. -The default is 8k. -.TP -.B -Z -Do not zero the index. -Using this option reduces the formatting time -but should only be used when it is known that the file was already zeroed. -.PD -.PP -.I Rdarena -extracts the named -.I arena -from the arena partition -.I arenapart -and writes this arena to standard output. -This command is typically used to back up an arena to external media. -The -.B -v -option generates more verbose output on standard error. -.PP -.I Wrarena -writes the blocks contained in the arena -.I arenafile -(typically, the output of -.IR rdarena ) -to a Venti server. -It is typically used to reinitialize a Venti server from backups of the arenas. -For example, -.IP -.EX -venti/rdarena /dev/sdC0/arenas arena.0 >external.media -venti/wrarena -h venti2 external.media -.EE -.LP -writes the blocks contained in -.B arena.0 -to the Venti server -.B venti2 -(typically not the one using -.BR /dev/sdC0/arenas ). -.PP -The -.B -o -option specifies that the arena starts at byte -.I fileoffset -(default -.BR 0 ) -in -.I arenafile . -This is useful for reading directly from -the Venti arena partition: -.IP -.EX -venti/wrarena -h venti2 -o 335872 /dev/sdC0/arenas -.EE -.LP -(In this example, 335872 is the offset shown in the Venti -server's index list (344064) minus one block (8192). -You will need to substitute your own arena offsets -and block size.) -.PP -Finally, the optional -.I offset -argument specifies that the writing should begin with the -clump starting at -.I offset -within the arena. -.I Wrarena -prints the offset it stopped at (because there were no more data blocks). -This could be used to incrementally back up a Venti server -to another Venti server: -.IP -.EX -last=`{cat last} -venti/wrarena -h venti2 -o 335872 /dev/sdC0/arenas $last >output -awk '/^end offset/ { print $3 }' offset >last -.EE -.LP -Of course, one would need to add wrapper code to keep track -of which arenas have been processed. -See -.B /sys/src/cmd/venti/backup.example -for a version that does this. -.PP -.I Read -and -.I write -read and write blocks from a running Venti server. -They are intended to ease debugging of the server. -The default -.I host -is the environment variable -.BR $venti , -followed by the network metaname -.BR $venti . -The -.I type -is the decimal type of block to be read or written. -If no -.I type -is specified for -.I read , -all types are tried, and a command-line is printed to -show the type that eventually worked. -If no -.I type -is specified for -.I write , -.B VtDataType -(13) -is used. -.I Read -reads the block named by -.I score -(a SHA1 hash) -from the Venti server and writes it to standard output. -.I Write -reads a block from standard input and attempts to write -it to the Venti server. -If successful, it prints the score of the block on the server. -.PP -.I Copy -walks the entire tree of blocks rooted at -.I score , -copying all the blocks visited during the walk from -the Venti server at network address -.I src -to the Venti server at network address -.I dst . -If -.I type -(a decimal block type for -.IR score ) -is omitted, all types will be tried in sequence -until one is found that works. -The -.B -f -flag runs the copy in ``fast'' mode: if a block is already on -.IR dst , -the walk does not descend below it, on the assumption that all its -children are also already on -.IR dst . -Without this flag, the copy often transfers many times more -data than necessary. -.PP -To make it easier to bootstrap servers, the configuration -file can be stored at the beginning of any Venti partitions using -.IR conf . -A partition so branded with a configuration file can -be used in place of a configuration file when invoking any -of the venti commands. -By default, -.I conf -prints the configuration stored in -.IR partition . -When invoked with the -.B -w -flag, -.I conf -reads a configuration file from -.I configfile -(or else standard input) -and stores it in -.IR partition . -.SH SOURCE -.B /sys/src/cmd/venti -.SH "SEE ALSO" -.IR venti (8), -.IR venti.conf (6) -.SH BUGS -.I Buildindex -should allow an individual index section to be rebuilt. -The merge sort could be performed in the space used to store the -index rather than requiring a temporary file. -- cgit v1.2.3