maximum MAXBSIZE

Rick Macklem rmacklem at uoguelph.ca
Tue Jan 7 22:48:00 UTC 2020


Hans Petter Selasky wrote:
>On 2020-01-07 22:12, Wojciech Puchar wrote:
>> default MAXBSIZE is 128kB. badly low for todays magnetic disks.
>>
>> i have it set to 2MB on all computers that have magnetic disks. Great
>> improvement with large files. especially when more than one are
>> read/wrote in parallel. And no problems experienced
>>
>> But for optimal performance MAXBSIZE should be transfered in few times
>> longer than average seek time. todays disk do 200-250MB/s so 2MB is
>> transfered below 10ms.
>>
>> 8-16MB seems like good choice. is there any reason not to set it that high?
>
>Old disk may not support it, especially USB 1.0/2.0 disks.
I also thought it was limited to MAXPHYS, but maybe I'm only thinking of the NFS
specific case?

rick


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