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emFile Benchmark and Footprint |
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Performance
A benchmark is used to measure the speed of the software
on available targets. This benchmark is in no way complete, but it gives
an approximation of the length of time required for common operations
on various targets.
Configuration and performance table
All values are in KBytes/sec.
| System |
Medium |
W0 |
W1 |
R |
| ARM 7 (50 MHz) |
Hard drive |
660 |
660 |
680 |
| ARM 7 (50 MHz) |
Compact Flash, 64MB, Toshiba, IDE mode |
1452 |
1452 |
1387 |
| ARM 7 (50 MHz) |
Compact Flash, 64MB, Toshiba, mem-mapped |
2368 |
2368 |
2206 |
| ARM 7 (50 MHz) |
MMC / SD using SPI with 12MHz |
695 |
711 |
1015 |
| ARM 7 (50 MHz) |
SMC |
26 |
26 |
495 |
| ARM 7 (33 MHz) |
NOR flash |
23 |
22 |
941 |
| ARM 7 (50 MHz) |
RAM disk |
4000 |
4000 |
4571 |
Description of the performance tests
The performance tests are executed as described and
in the order below.
W0: Writing
Writing data to a freshly formatted medium in chunks
of 64kBytes, using 80% of the capacity of the medium but no more than
3.2MByte.
W1: Writing
Writing data to a medium in chunks of 64kBytes, using
80% of the capacity of the medium but no more than 3.2MByte.
R: Reading
Reading data from a freshly formatted medium in chunks
of 64kBytes. using 80% of the capacity of the medium but no more than
3.2MByte.
CLICK HERE for Ordering Information.
Memory footprint
The file system is designed to fit many kinds of embedded
design requirements. Several features can be excluded from build to get
a minimal system that can efficiently access any FAT media.
In the following section memory usage for different typical 16 and 32-
bit systems is listed.
Please note that the values are valid for the given approximate values.
Features can affect the size of others. For example if FAT32 is deactivated,
the format function gets smaller because the 32 bit specific part of format
is not added into the compilation.
This minimal configuration supports FAT12/16, but has no media format
features, no directory support, no free disk space function (DiskInfo)
and only one file can be opened at a time:
The configuration file (FS_Conf.h) looks as follows:
| #define FS_POSIX_DIR_SUPPORT |
0 |
| #define FS_FAT_NOFORMAT |
1 |
| #define FS_FAT_DISKINFO |
0 |
| #define FS_FAT_NOFAT32 |
1 |
| #define FS_MAXOPEN |
1 |
16-bit CPUs
System
| Detail |
Description |
| CPU |
M16C |
| Tool chain |
IAR Workbench for M16C V2.12A |
| Memory Model |
Data model: Near pointer; Constants: near memory |
| Compiler options |
Highest size optimization |
| Device driver |
MMC/SD driver |
Memory requirements
| Detail |
ROM [Bytes] |
RAM [Bytes] |
| Minimal file system |
11384 |
1122 |
| MMC/SD driver |
+2172 |
528 |
| Additional support for |
| Directory |
+2654 |
+1310 (for each directory) |
| (Auto) format |
+2175 |
0 |
| Diskinfo |
+758 |
0 |
| FAT32 |
+658 |
0 |
| |
| Additional open files |
0 |
1060 |
32-bit CPUs
System
| Detail |
Description |
| CPU |
ARM 7 |
| Tool chain |
IAR Workbench for ARM V4.11A |
| Memory Model |
ARM7, thumb instructions; no interwork; |
| Compiler options |
Highest size optimization; |
| Device driver |
MMC/SD driver |
Memory requirements
| Detail |
ROM [Bytes] |
RAM [Bytes] |
| Minimal file system |
10298 |
1129 |
| MMC/SD driver |
+2358 |
532 |
| Additional support for |
| Directory |
+2208 |
+1328 (for each directory) |
| (Auto) format |
+2056 |
0 |
| Diskinfo |
488 |
0 |
| FAT32 |
352 |
0 |
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| Additional open files |
0 |
1068 |
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