Lines Matching full:system

30 New file system organization
32 In the new file system organization (as in the
33 old file system organization),
35 A file system is described by its super-block,
36 located at the beginning of the file system's disk partition.
39 This is done when the file system is created;
49 the minimum size of a file system block is 4096 bytes.
50 The size of file system blocks can be any power of two
52 The block size of a file system is recorded in the
53 file system's super-block
55 to be simultaneously accessible on the same system.
57 the file system is created;
58 it cannot be subsequently changed without rebuilding the file system.
60 The new file system organization divides a disk partition
72 the traditional file system's free list.
74 is allocated at file system creation time.
104 the cylinder group information begin on a file system block boundary.
105 To start the cylinder group on a file system block boundary,
109 Without knowing the size of the file system blocks,
110 the system would not know what roundup function to use
117 in a single disk transaction, greatly increasing file system throughput.
118 As an example, consider a file in the new file system
120 In the old file system this file would be composed of 1024 byte blocks.
122 system may transfer up to four times as much information per
132 Table 1 shows the effect of file system
133 block size on the amount of wasted space in the file system.
149 828.7 Mb	6.9	Data + inodes, 512 byte block UNIX file system
150 866.5 Mb	11.8	Data + inodes, 1024 byte block UNIX file system
151 948.5 Mb	22.4	Data + inodes, 2048 byte block UNIX file system
152 1128.3 Mb	45.6	Data + inodes, 4096 byte block UNIX file system
161 45.6% waste with 4096 byte file system blocks.
165 The new file system accomplishes this goal by allowing the division
166 of a single file system block into one or more
168 The file system fragment size is specified
169 at the time that the file system is created;
170 each file system block can optionally be broken into
179 Figure 1 shows a piece of a map from a 4096/1024 file system.
189 Figure 1 \- Example layout of blocks and fragments in a 4096/1024 file system.
204 On a file system with a block size of 4096 bytes
208 If a file system block must be fragmented to obtain
213 a 4096/1024 byte file system.
223 system call.
224 Each time data is written to a file, the system checks to see if
277 the same system,
278 the file system interface has been extended to provide
280 For files the optimal size is the block size of the file system
288 certain system utilities such as archivers and loaders
290 and need the highest possible file system bandwidth.
292 The amount of wasted space in the 4096/1024 byte new file system
294 1024 byte old file system organization.
295 A file system with 4096 byte blocks and 512 byte fragments
297 block UNIX file system.
298 The new file system uses less space
306 when a new file system's fragment size
307 equals an old file system's block size.
310 a file system cannot be kept completely full.
311 For each file system there is a parameter, termed
313 gives the minimum acceptable percentage of file system
316 only the system administrator can continue to allocate blocks.
318 even when the file system is mounted and active.
322 the file system throughput tends to be cut in half,
323 because of the inability of the file system to localize
325 If a file system's performance degrades because
336 an old 1024 byte UNIX file system is roughly
337 comparable to a new 4096/512 byte file system
339 (Compare 11.8% wasted with the old file system
341 new file system.)
343 File system parameterization
346 the old file system ignores the parameters of the underlying hardware.
350 A goal of the new file system is to parameterize the
361 Each file system is parameterized so that it can be
366 the new file system tries to allocate new blocks
373 depending on system characteristics.
418 the system first looks through the summary counts for a rotational
429 even when the file system is mounted and active.
430 If a file system is parameterized to lay out blocks with
432 and the disk pack is then moved to a system that has a
437 the file system can be parameterized for it
446 The file system layout policies are divided into two distinct parts.
447 At the top level are global policies that use file system
460 Two methods for improving file system performance are to increase
475 resembling the old file system.
504 In contrast, the old file system typically requires
527 at which a file on a 4096 byte block file system first
533 In observing the new file system in day to day use, the heuristics appear