[ofa-general] max_mr limit

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Rajouri Jammu wrote:
> The HCA I'm using reports max_mr = 131056.
>
> Our application needs large number of memory regions, much more than 
> the 128K limit.
>
> Is there a way to increase this limit? 
> I suppose it's bound by memory on the HCA. Is there an HCA that can 
> use host memory to increase the number of MRs that can be supported.
>
Which HCA you are using?
In mlx4 and mthca drivers there are modules parameters to change the 
amount of memory regions (by enlarging the number of MPTs and MTTs)

for example:
mlx4:
   log_num_mpt:         log maximum number of memory protection table 
entries per HCA (default is 17; max is 20)
   log_num_mtt:         log maximum number of memory translation table 
segments per HCA (default is 20; max is 20)

mthca:
  num_mpt               - maximum number of memory protection table 
entries per HCA (int)
  num_mtt               - maximum number of memory translation table 
segments per HCA (int)

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