I have been searching in and out on google and the forum about the issue I am experiencing with Linux, with no luck so far.
This is my system:
System: Host: wally Kernel: 3.13.0-37-generic x86_64 (64 bit) Desktop: Gnome Distro: Linux Mint 17.1 Rebecca Machine: System: Hewlett-Packard (portable) product: HP EliteBook Folio 9470m version: A1029D1102 Mobo: Hewlett-Packard model: 18DF version: KBC Version 62.17 Bios: Hewlett-Packard version: 68IBD Ver. F.46 date: 07/16/2013
I have an MMC card reader with a 128Gb card http://www.amazon.co.uk/dp/B00OD712HG/ref=pe_385721_51767431_TE_dp_1
The very same laptop can read and write at a considerable higher speed with Windows though.
Here are more info:
~ cat /sys/kernel/debug/mmc0/ios clock: 25000000 Hz actual clock: 25000000 Hz vdd: 21 (3.3 ~ 3.4 V) bus mode: 2 (push-pull) chip select: 0 (don't care) power mode: 2 (on) bus width: 2 (4 bits) timing spec: 0 (legacy) signal voltage: 0 (3.30 V) (while writing) ~ cat /proc/interrupts | grep mmc 18: 416899 327705 150854 74913 IR-IO-APIC-fasteoi mmc0 dmesg | grep mmc [ 3.374525] mmc0: no vqmmc regulator found [ 3.374530] mmc0: no vmmc regulator found [ 3.374669] mmc0: SDHCI controller on PCI [0000:02:00.0] using DMA [ 3.624502] mmc0: new SDXC card at address 59b4 [ 3.626966] mmcblk0: mmc0:59b4 119 GiB [ 3.628030] mmcblk0: p1 [ 141.158242] EXT4-fs (mmcblk0p1): mounted filesystem with ordered data mode. Opts: (null) lsmod | grep mmc mmc_block 35929 2
According to my understanding, I should have seen something like this this in dmesg
mmc0: new high speed SDHC card at address 0007
which I don't apparently.
Windows Perf: 60Mbps (read and write approx) Linux Perf: 6Mbps (10 times slower). While copying file over the SD card, I can see the CPU goes 60/70% wa status.
Am I doing something wrong? Any help is appreciated.