Hi hggomes,
Thank you very much for the information you posted. As the 1.0.1.4 CFE unblocks the overclocking it is of particular interest for me. Would you be so kind to provide the following information:
1. openssl performance for AES-256-CBC on overclocked RT-N66U for 650 and 660 MHz or any higher frequency (you posted only AES-128-CBC results)
2. does the overclocking changes the temperatures of radios?
3. do you have any idea what could be the highest reasonable (safe) overclock frequency?
4. any issues (may) resulting from overclocking
I am running OpenVPN server on my router and crypto performance is very important for me, so if the 1.0.1.4 CFE enables overclocking I will give it a try.
And one question to Merlin: Shall I re-flash your FW after changing of CFE?
My current CFE is 1.0.1.2
1.
admin@RT-N66U-C6C0:/tmp/home/root#
nvram get clkfreq
662,331,165
admin@RT-N66U-C6C0:/tmp/home/root#
cat /proc/cpuinfo
system type : Broadcom BCM5300 chip rev 1 pkg 0
processor : 0
cpu model : MIPS 74K V4.9
BogoMIPS : 330.95
wait instruction : no
microsecond timers : yes
tlb_entries : 64
extra interrupt vector : no
hardware watchpoint : yes
ASEs implemented : mips16 dsp
shadow register sets : 1
VCED exceptions : not available
VCEI exceptions : not available
unaligned_instructions : 380
dcache hits : 2147483648
dcache misses : 0
icache hits : 2147483648
icache misses : 0
instructions : 2147483648
admin@RT-N66U-C6C0:/tmp/home/root#
openssl speed aes-128-cbc
Doing aes-128 cbc for 3s on 16 size blocks:
2079582 aes-128 cbc's in 3.00s
Doing aes-128 cbc for 3s on 64 size blocks:
545241 aes-128 cbc's in 2.98s
Doing aes-128 cbc for 3s on 256 size blocks:
138968 aes-128 cbc's in 2.98s
Doing aes-128 cbc for 3s on 1024 size blocks:
35711 aes-128 cbc's in 3.00s
Doing aes-128 cbc for 3s on 8192 size blocks:
4463 aes-128 cbc's in 2.99s
OpenSSL 1.0.1h 5 Jun 2014
built on: Sun Jun 8 20:17:33 WEST 2014
options:bn(64,32) rc4(ptr,char) des(idx,cisc,2,long) aes(partial) idea(int) blowfish(ptr)
compiler: mipsel-uclibc-gcc -fPIC -DOPENSSL_PIC -DOPENSSL_THREADS -D_REENTRANT -DDSO_DLFCN -DHAVE_DLFCN_H -ffunction-sections -fdata-sections -DL_ENDIAN -DTERMIO -O3 -DLINUX26 -DCONFIG_BCMWL5 -DDEBUG_NOISY -DDEBUG_RCTEST -pipe -DBCMWPA2 -funit-at-a-time -Wno-pointer-sign -mtune=mips32r2 -mips32r2 -DRTCONFIG_NVRAM_64K -DLINUX_KERNEL_VERSION=132630 -DOPENSSL_SMALL_FOOTPRINT -fomit-frame-pointer -Wall -DSHA1_ASM -DSHA256_ASM -DAES_ASM
The 'numbers' are in 1000s of bytes per second processed.
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes
aes-128 cbc 11091.10k 11709.87k 11938.19k 12189.35k 12227.72k
admin@RT-N66U-C6C0:/tmp/home/root#
openssl speed aes-256-cbc
Doing aes-256 cbc for 3s on 16 size blocks:
1615079 aes-256 cbc's in 3.02s
Doing aes-256 cbc for 3s on 64 size blocks:
424612 aes-256 cbc's in 3.01s
Doing aes-256 cbc for 3s on 256 size blocks:
107727 aes-256 cbc's in 3.00s
Doing aes-256 cbc for 3s on 1024 size blocks:
27104 aes-256 cbc's in 3.00s
Doing aes-256 cbc for 3s on 8192 size blocks:
3388 aes-256 cbc's in 3.00s
OpenSSL 1.0.1h 5 Jun 2014
built on: Sun Jun 8 20:17:33 WEST 2014
options:bn(64,32) rc4(ptr,char) des(idx,cisc,2,long) aes(partial) idea(int) blowfish(ptr)
compiler: mipsel-uclibc-gcc -fPIC -DOPENSSL_PIC -DOPENSSL_THREADS -D_REENTRANT -DDSO_DLFCN -DHAVE_DLFCN_H -ffunction-sections -fdata-sections -DL_ENDIAN -DTERMIO -O3 -DLINUX26 -DCONFIG_BCMWL5 -DDEBUG_NOISY -DDEBUG_RCTEST -pipe -DBCMWPA2 -funit-at-a-time -Wno-pointer-sign -mtune=mips32r2 -mips32r2 -DRTCONFIG_NVRAM_64K -DLINUX_KERNEL_VERSION=132630 -DOPENSSL_SMALL_FOOTPRINT -fomit-frame-pointer -Wall -DSHA1_ASM -DSHA256_ASM -DAES_ASM
The 'numbers' are in 1000s of bytes per second processed.
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes
aes-256 cbc 8556.71k 9028.30k 9192.70k 9251.50k 9251.50k
If you want/need better performance with OpenSSL / OpenVPN you should try RT-AC56U or RT-AC68U, it has almost 4x times better performance, and even more if overclocked.
2. I didn't notice any changes on temperatures, i have double check it.
3. I guess "nvram set clkfreq=662,331,165" are the highest clocks.
4. You can have instability on the router, not sure if that's the case on RT-N66U because i'm using RT-AC68U, but you can do some testing and after some time at those speeds you will notice for sure if any instabilty exists or not.
Beside that CPU/DDR lifetime could be less, even it's not a problem in my opinion, it's only 10% overclocking so it does not have a big impact definitely. If CPU/DDR it's prepared to work let's say 15 years you will loose less then a year if so with the overclock, don't you worry about it