Performance issue in gnuradio version 3.10.1

[SHAKTHIVEL S 2021 Batch,PES University]

I tried running the Packet Commication example given in gnuradio
documentation using gr38 embedded block. It throwed me this error
"pagesize :error: no info; setting pagesize = 4096"
Although this is not an error strictly it reduced the performance of the
flowgraph drastically and I couldn't decode the message on the receiver
side.The constellation are overlapping and trying to move away slowly. Any
help would be appreciated
Link to the site:
https://wiki.gnuradio.org/index.php/Packet_Communications?ver1=3.8