Improved benchmarks

Author: mikaelpatel

README.md

@@ -2,8 +2,8 @@
 
 The Storage library for Arduino is designed to abstract handling of
 external memory, and allow block read/write and streaming of data. The
-library includes device drivers for SPI SRAM (23LC1024), 2-Wire EEPROM
-(AT24CXX) and internal EEPROM.
+library includes device drivers for SPI SRAM (23LC512/1024), 2-Wire
+EEPROM (AT24CXX) and internal EEPROM.
 
 Version: 1.0
 
@@ -16,27 +16,29 @@ Version: 1.0
 ## Drivers
 
 * [2-Wire EEPROM, AT24CXX](./src/Driver/AT24CXX.h)
+* [512 Kbit Serial SRAM, 23LC512](./src/Driver/MC23LC512.h)
 * [1 Mbit Serial SRAM, 23LC1024](./src/Driver/MC23LC1024.h)
 * [Internal EEPROM, EEPROM](./src/Driver/EEPROM.h)
 
 ## Example Sketches
 
-* [Benchmarks](./examples/Benchmarks) measurements of characteristics.
+* [Benchmarks](./examples/Benchmarks) measurement of characteristics.
 * [Block](./examples/Block) read/write eeprom blocks.
 * [Persistent](./examples/Persistent) read/write configuration.
 * [Stream](./examples/Stream) storage as a print stream.
 * [Vector](./examples/Vector) handling large sample vectors.
 
 ## Benchmarks
 
-### AT24C32, 2-Wire EEPROM
+### AT24C32, 2-Wire EEPROM, 100 KHz
 #### Read
 N | us | us/byte | kbyte/s
 --|----|---------|--------
 1 | 528 | 528.00 | 1.89
 10 | 1352 | 135.20 | 7.40
 100 | 9680 | 96.80 | 10.33
 1000 | 93128 | 93.13 | 10.74
+
 #### Write
 N | us | us/byte | kbyte/s
 --|----|---------|--------
@@ -46,19 +48,21 @@ N | us | us/byte | kbyte/s
 1000 | 206280 | 206.28 | 4.85
 
 Note: 1) The read/write operations have a three byte header (8-bit
-command, and 16-bit address), 2) Write performance increases up to
+command, and 16-bit address). 2) Write performance increases up to
 page size. When the block size is larger than the page size the write
 operation will wait for the device to complete the page write. Typical
-max 10 ms per page.
+max 5-10 ms per page. 3) 400 KHz (and even 800 KHz) clock can be
+used.
 
-### 23LC1024, SPI SRAM
+### 23LC1024, SPI SRAM, 8 MHz
 #### Read
 N | us | us/byte | kbyte/s
 --|----|---------|--------
 1 | 24 | 24.00 | 41.67
-10 | 40 | 4.00 | 250.00
-100 | 172 | 1.72 | 581.40
-1000 | 1532 | 1.53 | 652.74
+10 | 36 | 3.60 | 277.78
+100 | 156 | 1.56 | 641.03
+1000 | 1344 | 1.34 | 744.05
+
 #### Write
 N | us | us/byte | kbyte/s
 --|----|---------|--------

examples/Benchmarks/AT24CXX/AT24CXX.ino

@@ -1,6 +1,7 @@
-/*
- * eeprom.SIZE = 4096
- *
+/* Results:
+ * ----------------------------------------
+ * twi@100kHz
+ * ----------------------------------------
  * write(N, us, us/byte, kbyte/s)
  * 1, 408, 408.00, 2.45
  * 10, 1236, 123.60, 8.09
@@ -12,12 +13,43 @@
  * 10, 1352, 135.20, 7.40
  * 100, 9680, 96.80, 10.33
  * 1000, 93128, 93.13, 10.74
+ *
+ * ----------------------------------------
+ * twi@400kHz
+ * ----------------------------------------
+ * write(N, us, us/byte, kbyte/s)
+ * 1, 132, 132.00, 7.58
+ * 10, 352, 35.20, 28.41
+ * 100, 12288, 122.88, 8.14
+ * 1000, 125164, 125.16, 7.99
+ *
+ * read(N, us, us/byte, kbyte/s)
+ * 1, 168, 168.00, 5.95
+ * 10, 392, 39.20, 25.51
+ * 100, 2640, 26.40, 37.88
+ * 1000, 25152, 25.15, 39.76
+ *
+ * ----------------------------------------
+ * twi@800kHz
+ * ----------------------------------------
+ * write(N, us, us/byte, kbyte/s)
+ * 1, 88, 88.00, 11.36
+ * 10, 204, 20.40, 49.02
+ * 100, 10916, 109.16, 9.16
+ * 1000, 112656, 112.66, 8.88
+ *
+ * read(N, us, us/byte, kbyte/s)
+ * 1, 104, 104.00, 9.62
+ * 10, 228, 22.80, 43.86
+ * 100, 1468, 14.68, 68.12
+ * 1000, 13916, 13.92, 71.86
  */
 
 #include "Storage.h"
 #include "TWI.h"
 #include "Driver/AT24CXX.h"
 
+// Configure: TWI bus manager variant
 // #define USE_SOFTWARE_TWI
 #define USE_HARDWARE_TWI
 
@@ -27,15 +59,24 @@
 Software::TWI<BOARD::D6, BOARD::D7> twi;
 #elif defined(USE_HARDWARE_TWI)
 #include "Hardware/TWI.h"
-Hardware::TWI twi;
+// Configure: Hardware TWI bus clock frequency
+//
+#define FREQ 800000UL
+// #define FREQ 400000UL
+// #define FREQ 100000UL
+Hardware::TWI twi(FREQ);
 #endif
 
 // EEPROM external storage
 AT24C32 eeprom(twi);
 
 // Local memory buffer
 const int BUF_MAX = 1000;
-static uint8_t buf[BUF_MAX];
+uint8_t buf[BUF_MAX];
+
+// Buffer sizes
+const int N_MAX = 6;
+const int N[N_MAX] = { 1, 10, eeprom.PAGE_MAX, eeprom.PAGE_MAX*2, 100, 1000 };
 
 void setup()
 {
@@ -46,19 +87,28 @@ void setup()
 void loop()
 {
   static uint8_t n = 0;
+  uint32_t start;
+  uint32_t us;
+  float uspb;
+
   for (int i = 0; i < BUF_MAX; i++) buf[i] = n + i;
 
-  Serial.print(F("eeprom.SIZE = "));
-  Serial.println(eeprom.SIZE);
   Serial.println();
+  Serial.print(F("twi.FREQ(kHz) = "));
+  Serial.println(FREQ / 1000);
+  Serial.print(F("eeprom.SIZE(kbyte) = "));
+  Serial.println(eeprom.SIZE / 1024);
+  Serial.println();
+
+  // Benchmark#1: Measure write with increasing buffer size
   Serial.println(F("write(N, us, us/byte, kbyte/s)"));
   Serial.flush();
-  for (int i = 1; i < 10000; i *= 10) {
-    uint32_t start = micros();
-    eeprom.write(0x0000, buf, i);
-    uint32_t us = micros() - start;
-    float uspb = ((float) us) / i;
-    Serial.print(i);
+  for (int i = 0; i < N_MAX; i++) {
+    start = micros();
+    eeprom.write(0x0000, buf, N[i]);
+    us = micros() - start;
+    uspb = ((float) us) / N[i];
+    Serial.print(N[i]);
     Serial.print(F(", "));
     Serial.print(us);
     Serial.print(F(", "));
@@ -71,14 +121,15 @@ void loop()
 
   for (int i = 0; i < BUF_MAX; i++) buf[i] = 0;
 
+  // Benchmark#2: Measure read with increasing buffer size
   Serial.println(F("read(N, us, us/byte, kbyte/s)"));
   Serial.flush();
-  for (int i = 1; i < 10000; i *= 10) {
-    uint32_t start = micros();
-    eeprom.read(buf, 0x0000, i);
-    uint32_t us = micros() - start;
-    float uspb = ((float) us) / i;
-    Serial.print(i);
+  for (int i = 0; i < N_MAX; i++) {
+    start = micros();
+    eeprom.read(buf, 0x0000, N[i]);
+    us = micros() - start;
+    uspb = ((float) us) / N[i];
+    Serial.print(N[i]);
     Serial.print(F(", "));
     Serial.print(us);
     Serial.print(F(", "));
@@ -87,7 +138,6 @@ void loop()
     Serial.println(1000 / uspb);
     Serial.flush();
   }
-  Serial.println();
 
   for (int i = 0; i < BUF_MAX; i++) {
     if (buf[i] != ((n + i) & 0xff)) {

examples/Benchmarks/EEPROM/EEPROM.ino

@@ -38,6 +38,8 @@ void loop()
   Serial.print(F("eeprom.SIZE: "));
   Serial.println(eeprom.SIZE);
   Serial.println();
+
+  // Benchmark#1: Measure write with increasing buffer size
   Serial.println(F("write(N, us, us/byte, kbyte/s)"));
   Serial.flush();
   for (int i = 1; i < 10000; i *= 10) {
@@ -58,6 +60,7 @@ void loop()
 
   for (int i = 0; i < BUF_MAX; i++) buf[i] = 0;
 
+  // Benchmark#2: Measure read with increasing buffer size
   Serial.println(F("read(N, us, us/byte, kbyte/s)"));
   Serial.flush();
   for (int i = 1; i < 10000; i *= 10) {

examples/Benchmarks/MC23LC1024/MC23LC1024.ino

@@ -1,17 +1,18 @@
 /*
- * sram.SIZE = 131072
+ * spi.FREQ(MHz) = 8
+ * sram.SIZE(kbyte) = 128
  *
  * write(N, us, us/byte, kbyte/s)
  * 1, 24, 24.00, 41.67
- * 10, 36, 3.60, 277.78
+ * 10, 40, 4.00, 250.00
  * 100, 172, 1.72, 581.40
  * 1000, 1468, 1.47, 681.20
  *
  * read(N, us, us/byte, kbyte/s)
  * 1, 24, 24.00, 41.67
- * 10, 40, 4.00, 250.00
- * 100, 172, 1.72, 581.40
- * 1000, 1532, 1.53, 652.74
+ * 10, 36, 3.60, 277.78
+ * 100, 156, 1.56, 641.03
+ * 1000, 1344, 1.34, 744.05
  */
 
 #include "Storage.h"
@@ -52,9 +53,13 @@ void loop()
   static uint8_t n = 0;
   for (int i = 0; i < BUF_MAX; i++) buf[i] = n + i;
 
-  Serial.print(F("sram.SIZE = "));
-  Serial.println(sram.SIZE);
   Serial.println();
+  Serial.println(F("spi.FREQ(MHz) = 8"));
+  Serial.print(F("sram.SIZE(kbyte) = "));
+  Serial.println(sram.SIZE / 1024);
+  Serial.println();
+
+  // Benchmark#1: Measure write with increasing buffer size
   Serial.println(F("write(N, us, us/byte, kbyte/s)"));
   Serial.flush();
   for (int i = 1; i < 10000; i *= 10) {
@@ -75,6 +80,7 @@ void loop()
 
   for (int i = 0; i < BUF_MAX; i++) buf[i] = 0;
 
+  // Benchmark#2: Measure read with increasing buffer size
   Serial.println(F("read(N, us, us/byte, kbyte/s)"));
   Serial.flush();
   for (int i = 1; i < 10000; i *= 10) {
@@ -91,7 +97,6 @@ void loop()
     Serial.println(1000 / uspb);
     Serial.flush();
   }
-  Serial.println();
 
   for (int i = 0; i < BUF_MAX; i++) {
     if (buf[i] != ((n + i) & 0xff)) {

library.properties

@@ -3,7 +3,7 @@ version=1.0
 author=Mikael Patel
 maintainer=Mikael Patel <[email protected]>
 sentence=External Memory Storage library for Arduino.
-paragraph=This library is designed to abstract handling of external memory and allow block read/write and streaming of data. The library includes device drivers for SPI SRAM (23LC1024), 2-Wire EEPROM (AT24CXX) and internal EEPROM.
+paragraph=This library is designed to abstract handling of external memory and allow block read/write and streaming of data. The library includes device drivers for SPI SRAM (23LC512/23LC1024), 2-Wire EEPROM (AT24CXX) and internal EEPROM.
 category=Data Storage
 url=https://github.com/mikaelpatel/Arduino-Storage
 architectures=avr

mainpage.dox

@@ -1,10 +1,10 @@
 /** @mainpage Arduino-Storage
 
 The Storage library for Arduino is designed to abstract handling of
-external memory, and allow block read/write (Storage::Block) and
-streaming of data (Storage::Stream). The library includes device
-drivers for SPI SRAM (MC23LC1024), 2-Wire EEPROM (AT24CXX) and
-internal EEPROM.
+external memory. It allows block and vector read/write
+(Storage::Block) and streaming of data (Storage::Stream). The library
+includes device drivers for SPI SRAM (MC23LC1024, MC23LC512), 2-Wire
+EEPROM (AT24CXX) and internal EEPROM.
 
 Version: 1.0
 */