Changeset: 6649fc91719a for MonetDB
URL: http://dev.monetdb.org/hg/MonetDB?cmd=changeset;node=6649fc91719a
Modified Files:
gdk/gdk_bbp.c
gdk/gdk_bbp.h
Branch: headless
Log Message:
Documentation should only go to .c file.
diffs (86 lines):
diff --git a/gdk/gdk_bbp.c b/gdk/gdk_bbp.c
--- a/gdk/gdk_bbp.c
+++ b/gdk/gdk_bbp.c
@@ -15,8 +15,9 @@
* Portions created by CWI are Copyright (C) 1997-July 2008 CWI.
* Copyright August 2008-2011 MonetDB B.V.
* All Rights Reserved.
- * @
- *
+ */
+
+/*
* @f gdk_bbp
* @a M. L. Kersten, P. Boncz, N. J. Nes
* @* BAT Buffer Pool (BBP)
diff --git a/gdk/gdk_bbp.h b/gdk/gdk_bbp.h
--- a/gdk/gdk_bbp.h
+++ b/gdk/gdk_bbp.h
@@ -17,67 +17,6 @@
* All Rights Reserved.
*/
-/*
- * @f gdk_bbp
- * @a M. L. Kersten, P. Boncz, N. J. Nes
- * @* BAT Buffer Pool (BBP)
- * The BATs created and loaded are collected in a BAT buffer pool.
- * The Bat Buffer Pool has a number of functions:
- * @table @code
- *
- * @item administration and lookup
- * The BBP is a directory which contains status information about all known
BATs.
- * This interface may be used very heavily, by data-intensive applications.
- * To eliminate all overhead, read-only access to the BBP may be done by
- * table-lookups. The integer index type for these lookups is @emph{bat}, as
- * retrieved by @emph{BBPcacheid(b)}. The @emph{bat} zero is reserved for the
nil bat.
- *
- * @item persistence
- * The BBP is made persistent by saving it to the dictionary file
- * called @emph{BBP.dir} in the database.
- *
- * When the number of BATs rises, having all files in one directory
- * becomes a bottleneck. The BBP therefore implements a scheme that
distributes
- * all BATs in a growing directory tree with at most 64 BATs stored in one
node.
- *
- * @item buffer management
- * The BBP is responsible for loading and saving of BATs to disk. It also
- * contains routines to unload BATs from memory when memory resources
- * get scarce. For this purpose, it administers BAT memory reference
- * counts (to know which BATs can be unloaded) and BAT usage statistics
- * (it unloads the least recently used BATs).
- *
- * @item recovery
- * When the database is closed or during a run-time syncpoint, the system
- * tables must be written to disk in a safe way, that is immune for system
- * failures (like disk full). To do so, the BBP implements an atomic commit and
- * recovery protocol: first all files to be overwritten are moved to a BACKUP/
- * dir. If that succeeds, the writes are done. If that also fully succeeds
- * the BACKUP/ dir is renamed to DELETE_ME/ and subsequently deleted.
- * If not, all files in BACKUP/ are moved back to their original location.
- *
- * @item unloading
- * Bats which have a logical reference (ie. a lrefs > 0) but no memory
- * reference (refcnt == 0) can be unloaded. Unloading dirty bats means,
- * moving the original (committed version) to the BACKUP/ dir and saving
- * the bat. This complicates the commit and recovery/abort issues.
- * The commit has to check if the bat is already moved. And The recovery
- * has to always move back the files from the BACKUP/ dir.
- *
- * @item reference counting
- * Bats use have two kinds of references: logical and physical (pointer) ones.
- * Both are administered with the BBPincref/BBPdecref routines. For
- * backward compatibility, we maintain BBPfix/BBPunfix as shorthands
- * for the adjusting the pointer references.
- *
- * @item share counting
- * Views use the heaps of there parent bats. To save guard this, the
- * parent has a shared counter, which is incremented and decremented
- * using BBPshare and BBPunshare. These functions make sure the
- * parent is memory resident as required because of the 'pointer' sharing.
- * @end table
- */
-
#ifndef _GDK_BBP_H_
#define _GDK_BBP_H_
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