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+<!-- This HTML file has been created by texi2html 1.29
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+<TITLE>Analysis of the Ext2fs structure - Allocation algorithms</TITLE>
+<P>Go to the <A HREF="ext2fs_8.html">previous</A>, <A HREF="ext2fs_10.html">next</A> section.<P>
+<H1><A NAME="SEC9" HREF="ext2fs_toc.html#SEC9">Allocation algorithms</A></H1>
+<P>
+Here are the allocation algorithms that ext2 file system managers
+<STRONG>must</STRONG> use. We are adamant on this point. Nowadays, many users
+use more than one operating system on the same computer. If more than
+one operating system use the same ext2 partition, they have to use the
+same allocation algorithms. If they do otherwise, what will happen is
+that one file system manager will undo the work of the other file system
+manager. It is useless to have a manager that uses highly efficient
+allocation algorithms if the other one does not bother with allocation
+and uses quick and dirty algorithms.
+<P>
+Here are the rules used to allocate new inodes:
+<P>
+<UL>
+<LI>the inode for a new file is allocated in the same group of the
+inode of its parent directory.
+<P>
+<LI>inodes are allocated equally between groups.
+</UL>
+<P>
+Here are the rules used to allocate new blocks:
+<P>
+<UL>
+<LI>a new block is allocated in the same group as its inode.
+<P>
+<LI>allocate consecutive sequences of blocks.
+</UL>
+<P>
+Of course, it may be sometimes impossible to abide by those rules. In
+this case, the manager may allocate the block or inode anywhere.
+<P>Go to the <A HREF="ext2fs_8.html">previous</A>, <A HREF="ext2fs_10.html">next</A> section.<P>