Low GPU load for dictionary attack
#1
Hello,
I have two hashing rigs, running on Ubuntu 14.04 LTS. Rig #1 has 4x Gigabyte R9 280x GPUs, Rig #2 has 4x MSI Twinfrozr III 7950 GPUs.

I use latest version of oclHashcat + hashtopus.

When I use mask brute force attack mode amdconfig shows continuous 99% load on every card, but for dictionary mode it drops to 70-95% and fluctuates.

Dictionary is quite big, 36 GB plain text, so I thought it's because hard drive. However I've been monitoring my hard drive (3 TB Seagate Barracuda 7200rpm) and I couldn't find any bottlenecks. During normal operation reading from drive takes maybe 5% of full speed, IOPS is on 30-50% level.

CPU is also good, 30-50% load.

It happens for both of my rigs.

So how comes it doesn't use full speed of my cards if there are no bottlenecks?

Well, at least I don't see them.

Any ideas?


Messages In This Thread
Low GPU load for dictionary attack - by oktar - 06-29-2015, 06:32 PM