Performance in HDTach

HDTach, chastised but indispensable, opens up the show.

First of all, I would like to point out the level of CPU utilization. The UDMA/133 protocol perceptibly lowers the CPU utilization for Samsung PL40. We saw this with the Maxtor drive very rarely, I should say. However, the new model didn’t catch up with its predecessor, which is no surprise considering its higher linear speeds.

Now, let’s learn the physical characteristics of the drives.

The average rotational latency time is about 4.17ms for all participating drives. By subtracting this value from the measured time we get the average seek time.

• Samsung PL40 – 9.6ms
• Maxtor 6E040L0 – 9.7ms
• Seagate 7200.7 – 10.8ms
• Samsung SP40 – 8.9ms
• IBM/Hitachi 180GXP – 8.9ms

The Seagate drive turns to be an outsider in terms of average access time, while Samsung PL40 did quite well and proved up to its specs. It is just a little slower than the predecessor. In fact, that is exactly how it should be: a low-profile drive must have a less powerful actuator, and the fashion for noiseless work brings about its own restrictions, too.

The next diagram shows the speeds of the drives.

As for burst read speed, Samsung PL40 is no record-breaker: working on UDMA/133, it is a tiny bit ahead of the UDMA/100 IBM/Hitachi disk. Anyway, the result is the same as that of the competitors, and better than by the predecessor. The new Samsung loses in average read speed to only the Maxtor drive. As for write speeds, we already know we shouldn’t trust HDTach here.

Now, let’s have a look at the internal platter organization of the drives. The diagram below shows their speeds converted into millions of bytes per second, as manufacturers specify them.

So, Samsung PL40 is a little slower on the edge of the platter than Seagate 7200.7, but a little faster in the two other categories. Its doubled data density resulted in a 25% linear speed growth. Still, the analogous platter from Maxtor is notably faster. However, high linear speed doesn’t necessarily mean higher performance at work. Moreover, it might have been achieved by packing less servo information per track, which usually leads to a reduced reliability and life term of the drive.

Summing up, I would say that Samsung PL40 won no nomination, but has never been the last. It shows stable and good results, which is very nice. Let’s see what it will show next.