I am writing a perl program that directly writes data on a raw partition, it is mission critical that it is written in order and at the time I write it, no buffering..

I am using sysopen, sysread, sysseek to do this.
I have set HANDLE->autoflush(1)
and I have set $| = 1;
It is obviously still buffering however as it completes writing 100 mb in 1024 bytes at a time alternating between the end and beggining of a 25gb partition in 2 seconds! HD's are bad for random access liek this, whereas flash drives are supposed to be better, it takes the flash drive 36 seconds for the same thing to occur!

In reply to Need writes to happen immediately. by exodist

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