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What are typical results for emmc read/write performance with 6sl?

Question asked by jayakumar2 on Aug 17, 2017
Latest reply on Aug 17, 2017 by igorpadykov



I'm working with an i.mx6sololite (6sl) board with a Micron MTFC16GAKAECN-2M emmc 5.0 chip. I am developing with Linux 4.1.15 BSP from NXP.


I'm trying to figure out if the performance numbers I'm getting for this board are reasonable or if there is a problem that is limiting performance.


With the emmc, I'm getting:

Timing buffered disk reads: 154 MB in 3.01 seconds = 51.21 MB/sec


Zero write, I'm getting about 28MB/s:

# time dd if=/dev/zero of=/dev/mmcblk1 bs=1M count=100
100+0 records in
100+0 records out

real 0m3.438s
user 0m0.000s
sys 0m0.670s


The main problem is to flash firmware (read+decompress from microsd, write to emmc) of about 2GB, it takes 7m30s which means effective read+write speed is about 5MB/s.


perf stat sleep 1

Performance counter stats for 'sleep 1':

2.830458 task-clock (msec) # 0.003 CPUs utilized
1 context-switches # 0.353 K/sec
0 cpu-migrations # 0.000 K/sec
42 page-faults # 0.015 M/sec
2216576 cycles # 0.783 GHz
0 stalled-cycles-frontend # 0.00% frontend cycles idle
0 stalled-cycles-backend # 0.00% backend cycles idle
0 instructions # 0.00 insns per cycle
0 branches # 0.000 K/sec
0 branch-misses # 0.00% of all branches

1.017062584 seconds time elapsed


mmc1: SDHCI controller on 2194000.usdhc [2194000.usdhc] using DMA
mmc1: MAN_BKOPS_EN bit is not set
mmc1: new DDR MMC card at address 0001
mmcblk1: mmc1:0001 R1J56L 13.7 GiB
mmcblk1boot0: mmc1:0001 R1J56L partition 1 4.00 MiB
mmcblk1boot1: mmc1:0001 R1J56L partition 2 4.00 MiB
mmcblk1rpmb: mmc1:0001 R1J56L partition 3 128 KiB