This module limits the number of IDs requested from the index per batch.
Some indices allow only a certain number of IDs per request (e.g. the Findex allows a maximum of 50 IDs).
Integrate the module in the modules directory of VuFind and activate it by adding LimitBatch to VUFIND_LOCAL_MODULES.
The limit is set by the record_batch_size setting in the [Index]block of the config.ini. Set it like this in your local file:
[Index]
record_batch_size = 100