oracular (8) makehistory.8.gz

Provided by: inn2_2.7.2-1_amd64 bug

NAME

       makehistory - Initialize or rebuild INN history database

SYNOPSIS

       makehistory [-abFIOSx] [-f filename] [-l count] [-L load-average] [-s size] [-T tmpdir]

DESCRIPTION

       makehistory rebuilds the history(5) text file, which contains a list of message-IDs of articles already
       seen by the server.  It can also be used to rebuild the overview database.  Note that even though the dbz
       indices for the history file are also rebuilt by makehistory, it is useful to run makedbz(8) after
       makehistory(8) in order to improve the efficiency of the indices (makehistory does not know how large to
       make the hash table at first run, unless the size is given by the -s flag).

       The default location of the history text file is pathdb/history; to specify an alternate location, use
       the -f flag.

       By default, makehistory will scan the entire spool, using the storage manager, and write a history line
       for every article.  To also generate overview information, use the -O flag.

       If a malformed article is found in the news spool, in a way which prevents its integration into the
       history or overview data, a log line will be output and the malformed article will just be skipped.

OVERVIEW REBUILD

       WARNING: If you're trying to rebuild the overview database, be sure to stop innd(8) and delete or zero
       out the existing database before you start for the best results.  An overview rebuild should not be done
       while the server is running.  Unless the existing overview is deleted, you may end up with problems like
       out-of-order overview entries, excessively large overview buffers, and the like.

       If ovmethod in inn.conf is "ovdb", you must have the ovdb processes running while rebuilding overview.
       ovdb needs them available while writing overview entries.  You can start them by hand separate from the
       rest of the server by running ovdb_init; see ovdb_init(8) for more details.

       Similarly, if ovmethod in inn.conf is "ovsqlite", you must have the ovsqlite-server process running while
       rebuilding overview.  See ovsqlite-server(8) for more details and how to start it by hand.

       Rebuilding overview data is as straight-forward as:

       1.  Checking that the configuration file of the new overview storage method is present in pathetc and
           fits your needs (buffindexed.conf, ovdb.conf or ovsqlite.conf).  Note that the tradindexed overview
           storage method does not have a dedicated configuration file.

       2.  Making sure that INN is stopped ("rc.news stop" as the news user, or whichever command you're using).

       3.  Setting the new overview storage method in the ovmethod parameter in inn.conf.

       4.  Making sure that the directory specified by the pathoverview parameter in inn.conf exists and is
           empty (or contains freshly created buffindexed buffers, if using that overview storage method).
           Otherwise, rename the current directory (to backup existing overview data) and re-create pathoverview
           as the news user.

       5.  Starting ovdb_init or ovsqlite-server as the news user if the new overview storage method is
           respectively ovdb or ovsqlite.

       6.  Running "makehistory -O -x -F" and waiting for the command to finish.  (You may notice a few logs
           about articles for which overview data cannot be inserted into the new overview storage method.  As
           long as there aren't tons of them, it is normal, notably because there is an internal limit in the
           length of overview data generated by makehistory, contrary to innd.  Unfortunately, these rare
           articles won't be present in the new overview.)

       7.  Stopping ovdb or ovsqlite helper programs if you started them during the previous steps (running
           "rc.news stop" as the news user will stop them; do not mind the messages related to the fact that the
           news server was not running).

       8.  Starting INN and checking the logs to make sure everything is fine.  You will normally notice that
           the active file is renumbered (rc.news takes care of that when run after an overview rebuild;
           otherwise, manually run "ctlinnd renumber ''").

OPTIONS

       -a  Append to the history file rather than generating a new one.  If you append to the main history file,
           make sure innd(8) is throttled or not running, or you can corrupt the history.

       -b  Delete any messages found in the spool that do not have valid Message-ID header fields in them.

       -F  Fork a separate process to flush overview data to disk rather than doing it directly.  The advantage
           of this is that it allows makehistory to continue to collect more data from the spool while the first
           batch of data is being written to the overview database.  The disadvantage is that up to twice as
           much temporary disk space will be used for the generated overview data.  This option only makes sense
           in combination with -O.  With buffindexed, the overchan program is invoked to write overview.

       -f filename
           Rather than writing directly to pathdb/history, instead write to filename, also in pathdb.

       -I  Don't store overview data for articles numbered lower than the lowest article number in active.  This
           is useful if there are for whatever reason old articles on disk that shouldn't be available to
           readers or put into the overview database.

       -l count
           This option specifies how many articles to process before writing the accumulated overview
           information out to the overview database.  The default is "10000".  Since overview write performance
           is faster with sorted data, each "batch" gets sorted.  Increasing the batch size with this option may
           further improve write performance, at the cost of longer sort times.  Also, temporary space will be
           needed to store the overview batches.  At a rough estimate, about 300 * count bytes of temporary
           space will be required (not counting temp files created by sort(1)).  See the description of the -T
           option for how to specify the temporary storage location.  This option has no effect with
           buffindexed, because buffindexed does not need sorted overview and no batching is done.

       -L load-average
           Temporarily pause activities if the system load average exceeds the specified level load-average.
           This allows makehistory to run on a system being used for other purposes without monopolizing system
           resources and thus making the response time for other applications unacceptably slow.  Using nice(1)
           does not help much for that because the problem comes from disk I/O usage, and ionice(1) is not
           always available or efficient.

       -O  Create the overview database as well as the history file.  Overview information is only required if
           the server supports readers; it is not needed for a transit-only server (see enableoverview in
           inn.conf(5)).  If you are using the buffindexed overview storage method, erase all of your overview
           buffers before running makehistory with -O.

       -S  Rather than storing the overview data into the overview database, just write it to standard output in
           a form suitable for feeding to overchan later if wished.  When this option is used, -F, -I, -l, and
           -T are ignored.  This option only makes sense in combination with -O.

       -s size
           Size the history database for approximately size key-value pairs (i.e. lines in history).  Accurately
           specifying the size is an optimization that will create a more efficient database.  (The size should
           be the estimated eventual number of articles, typically the size of the old history file, in lines.)

           By default, makehistory will create a database optimized for handling about 6,000,000 articles (or
           500,000 if the slower tagged hash format is used).  This size does not limit the number of articles
           the news server can store in its history file.  It will just get slower when that optimal size is
           exceeded, until the next run of news.daily which will appropriately resize it.

       -T tmpdir
           If -O is given, makehistory needs a location to write temporary overview data.  By default, it uses
           pathtmp, set in inn.conf, but if this option is given, the provided tmpdir is used instead.  This is
           also used for temporary files created by sort(1) (which is invoked in the process of writing overview
           information since sorted overview information writes faster).  By default, sort usually uses your
           system temporary directory; see the sort(1) man page on your system to be sure.

       -x  If this option is given, makehistory won't write out history file entries.  This is useful mostly for
           building overview without generating a new history file.

EXAMPLES

       Here's a typical example of rebuilding the entire history and overview database, removing broken articles
       in the news spool.  This uses the default temporary file locations and should be done while innd isn't
       running (or is throttled).

           makehistory -b -f history.n -O -l 30000 -I

       This will rebuild the overview (if using buffindexed, erase the existing overview buffers before running
       this command) and leave a new history file as "history.n" in pathdb.  To preserve all of the history
       entries from the old history file that correspond to rejected articles or expired articles, follow the
       above command with:

           cd <pathdb>
           awk 'NF == 2 { print }' < history >> history.n

       (replacing the path with your pathdb, if it isn't the default).  Then look over the new history file for
       problems and run:

           makedbz -s `wc -l < history.n` -f history.n

       Then rename all of the files matching "history.n.*" to "history.*", replacing the current history
       database and indices.  After that, it's safe to unthrottle innd.

       For a simpler example:

           makehistory -b -f history.n -I -O

       will scan the spool, removing broken articles and generating history and overview entries for articles
       missing from history.

       To pre-size the history file for 100,000,000 articles, and generate overview data at the same time, you
       may directly use the following command:

           makehistory -O -s 100000000

       You then do not need running makedbz as the history file has already been generated and optimized for the
       expected number of articles.

       To just rebuild overview:

           makehistory -O -x -F

FILES

       pathdb/history
           This is the default output file for makehistory.

       pathtmp
           Where temporary files are written unless -T is given.

HISTORY

       Originally written by Rich $alz <rsalz@uunet.uu.net> for InterNetNews and updated by various other people
       since.

SEE ALSO

       active(5), ctlinnd(8), history(5), inn.conf(5), innd(8), libinn_dbz(3), makedbz(8), ovdb_init(8),
       overchan(8), ovsqlite-server(8).