[Gen9 Android Development] carefreeway:
[MENTION=7284943]mikibou[/MENTION], what's your free space on internal eMMC card?

[MENTION=649119]silver_surfer30[/MENTION], what do you mean by "crypted wireless network"? WPA2 enabled on Wifi (with password entering on connection)? If it is that, then I had no such problems with WPA2.

[MENTION=5670369]BlackGunZ[/MENTION], I removed extra duplicates from files and I spotted that "echo 5 > /proc/sys/vm/dirty_background_ratio;" works only inside 99Performance file rather than inside init.archos_init.rc. This is strange. Maybe better try to use sysctl?

Also, I've read memory optimisation links you mentioned above and I think that setting min_free_kbytes=2884, just 92 above the default value on 512MB 8" device (2792 is default there) isn't so well. Franco's Dev Team Chris (osm0sis) set this value twice the default value of his old device. But he had old low RAM device then. This value is calculated in the kernel (mm/page_alloc.c) by the formula:

min_free_kbytes = sqrt(lowmem_kbytes * 16)

lowmem_kbytes is the amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL. That means that osm0sis had (2884/2)^2/16/1024=126.9 MB of free RAM allocatable memory device. That is why I think 2884 for 1GB devices is too low.

So, optimisation for this value would be twice the size of the default one. The default one is different on 512MB and 1GB devices. Also, device with the same amount of RAM may has different default values due to vram allocation (8" or 10.1"). For example, Archos set vram_size for a80s and a80h to 6 MB and for a101s and a101h to 7M + 832K (see arch/arm/mach-omap2/archos-fixup.c), which may affect the allocatable amount of RAM and hence the default amount of min_free_kbytes. On my device (512MB 8") twice the default value is 2792*2=5584. Also, Android reference about low RAM optimisation recommends to set this value is about 3 times the full-screen of 32 bpp buffers. We have 4 bits per pixel display matrix (see "dmesg|grep -i vram" and "dmesg|grep resolution|grep android_display " just after the device start). But it doesn't relayted to this threshold value. It means for 8" screen the following value for min_free_kbytes from Android recomendation:

3*1024*768*32/8/1024=9216.

And for 10.1" screen is the following value:

3*1280*800*32/8/1024=12000.

Also, it would be better to change the swappiness to 100. As long as we allocated zram zwap in RAM, it would be better to use it better instead of using it at 5%-40% level. Also, I would raise the amount of zram swap size to recommended value there (40% instead of 27.6% of available RAM):

https://01.org/android-ia/user-guides/android-memory-tuning-android-5.0-and-5.1

So, for 512MB devices it would be 43.18% of available RAM (200M of 463.17M).

P.S. BTW, do you guys have the following issue with IOW and mmcqd/0?

# top

User 9%, System 21%, IOW 69%, IRQ 0%

User 55 + Nice 2 + Sys 132 + Idle 0 + IOW 431 + IRQ 0 + SIRQ 1 = 621

PID PR CPU% S #THR VSS RSS PCY UID Name

71 0 12% S 1 0K 0K fg root mmcqd/0

2819 0 7% D 12 615840K 27656K bg u0_a19 com.google.android.googlequicksearchbox:search

29 1 2% S 1 0K 0K fg root kswapd0

2776 0 1% D 18 674072K 40060K bg u0_a47 com.google.android.talk

It was measured from adb shell at the moment of freezes on start of the device. It was taking several seconds to switch from one application to another at that moment. What's your IO speeds in AndroBench after "fstrim -v /data" and "fstrim -v /mnt/system " on this tablet?