Maximum Celerra nfs.v3xfersize for old NS20 running version 5.6.40-3

Hello.

We are migrating off an old Celerra NS20 that is running version 5.6.40-3, and would like to improve the the efficiency of the migration by increasing the NFS rsize/wsize, which is controlled by the Celerra nfs.v3xfersize parameter. This parameter is currently set at 32kb, the default.

For version 5.6.40-3, can the nfs.v3xfersize parameter be increased?  If so, to what maximum value?  The Linux clients being used are capable of a 1MB rsize/wsize. The earliest documentation that I can find related to increasing nfs.v3xfersize is for version 6.0+, so increasing the parameter for version 5.6.40-3 my not be possible.

If the value can be increased, can it be done on-line, and what would be the artifacts? Ideally, existing NFS mounts would continue to use the previous setting, and new client mount requests could negotiate a higher value.  Are there any additional settings that need to be added to the NFS share definition or export to allow for a larger rsize/wsize ... on this old version of DART

Thank you for your help.

Dave B.