Thanks, I will try others way to improve the performance. 2009/11/26 Matthew Wilcox <matthew@xxxxxx>: > On Wed, Nov 25, 2009 at 08:20:02PM +0100, J?r?my Cochoy wrote: >> Hello, >> >> There is something strange in iunique : what will happend if all inode >> between max_reserved+1 and (unsinged in)(0-1) ? Will it make an >> infinite loop or an interruption can happen and make an inode become >> free? > > Another process can free an inode while this loop is executing. > >> In that case, it will be better to stop search when counter overflow, no? > > If you have all four billion inodes allocated, you have significantly > bigger problems than this loop. For a start, at 600 bytes per inode, > I'd like to see your machine with 2.4TB of memory. Then there's the > size of your inode hash, and the depth of the chains within it. > >> Will it not be better to use a field max_ino_used (in superblock, for >> exemple) where we store the last inode allocated with iunique and make >> a search only if max_ino_used become to (unsigned)(-1) ? >> >> But, if iunique is here to provide a solution in order to generate >> unused inode in filesystem which have various inode number, it's >> better to use a list of used ino, in a short hash table which use the >> first 8 bits of the inode, always use the same function to create a >> new inode and look at the head if we can add a new inode with bigger >> ino and still in the range. (But i think filesystems developper prefer >> to write ther own functions in order to do that, no?) >> >> Well, if we want to stop in case of full inode filesystem, we can put >> the first condition in the head and add change return as : >> return inode->i_ino > max_reserved ? res : 0; // 0 might "i can't find >> an inode after max_reserved" > > Gloves. > > http://thedailywtf.com/Articles/The_Complicator_0x27_s_Gloves.aspx > > -- > Matthew Wilcox Intel Open Source Technology Centre > "Bill, look, we understand that you're interested in selling us this > operating system, but compare it to ours. We can't possibly take such > a retrograde step." > -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
