On Tue, 25 Jan 2005, Michael M�ller wrote: > Hi Michael!
> If I understand right what you are looking for you could give > Reiser-FS a try. I have one partition with Reiser. It stores my copy > of the freecddb files: many many small text files. I think he's looking for "dense" file support, which is like an mount option "nosparse" that doesn't exist. I would guess that the major selling point of "dense" file support is that once a file has been allocated, you can be guaranteed that all of the space necessary to store the file exists on disk. According to my tests, reiser actually does the worst of every filesystem I tested (with respect to overhead). reiserv4 does the best, with ext2/3 coming in a close second. I'm sure my test is flawed with only a 100MB "partition" to test with, as the default blocksizes, etc... are likely to be different on larger filesystems. This is what I did. I have 410 very small files (average size close to 1KB, most are less than that, with a very small number larger than 3K.) I made a new logical volume of 100MB, and formatted it with JFS, copied over the files, and ran: report disk usage in BLOCKS: du -s: 1684 report *actual* disk usage in BLOCKS du -s --apparent-size: 293 report disk usage in bytes du -s --block-size=1: 1724416 report *actual* disk usage in bytesk du -s --block-size=1 --apparent-size: 299600 1724416/299600 = 575% overhead. I repeated with other filesysems. In a table: fs -s -s+as -s +bs -s+bs+as overhead ----------------------------------------------------------- jfs: 1684 293 1724416 299600 575% reiser (v3): 1536 243 1572864 247888 634% ext3: 478 260 489472 265968 84% xfs: 1588 289 1626112 295916 549% reiser4: 346 229 353792 233671 51% As you can see, reiser4 had the least overhead, followed by ext3, jfs, xfs, then reiserv3. What is the cause of the overhead, or am I wrong entirely about it even *being* overhead? -- Jon Nelson <[EMAIL PROTECTED]>
