Differences

This shows you the differences between two versions of the page.

--- simple_sequential_baseline_test [2017/10/09 19:52] – admin
+++ simple_sequential_baseline_test [2019/06/28 18:45] – admin
@@ Line 16: / Line 16: @@
 You can reverse things to see what the read test looks like, things should be faster on reads in all cases with respect to the SSD:
-<code>$ time dd of=/dev/zero if=tstfile bs=2048k count=512 iflag=direct
+<code>$ time dd of=/dev/null if=tstfile bs=2048k count=512 iflag=direct
 +0 records in
 +0 records out
@@ Line 28: / Line 28: @@
 (testing the DRAM memory, and system in this case)
-<code>$ time dd of=/dev/zero if=tstfile bs=2048k count=512
+<code>$ time dd of=/dev/null if=tstfile bs=2048k count=512
 +0 records in
 +0 records out
@@ Line 40: / Line 40: @@
 <code>Direct write: 1073741824 bytes (1.1 GB) copied, 14.604 s, 73.5 MB/s
 Direct read:  1073741824 bytes (1.1 GB) copied, 16.7439 s, 64.1 MB/s
-Read cache:   1073741824 bytes (1.1 GB) copied, 12.6424 s, 84.9 MB/s
+Read cache:   1073741824 bytes (1.1 GB) copied, 0.354082 s, 3.0 GB/s
 </code>
@@ Line 68: / Line 69: @@
 Direct read:  1073741824 bytes (1.1 GB) copied, 47.0731 s, 22.8 MB/s
 Read cache:   1073741824 bytes (1.1 GB) copied, 49.5828 s, 21.7 MB/s
+===Raspberry Pi 4 Model B 4GB. Transcend 8GB microSD Ultimate 600x Class 10 UHS-I===
+<code>Direct write: 1073741824 bytes (1.1 GB, 1.0 GiB) copied, 53.5692 s, 20.0 MB/s
+Direct read:  1073741824 bytes (1.1 GB, 1.0 GiB) copied, 25.1142 s, 42.8 MB/s
+Read cache:   1073741824 bytes (1.1 GB, 1.0 GiB) copied, 1.49443 s, 718 MB/s
 </code>