PCAP load speed difference between Wireshark and tshark

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I have some PCAP files from which I'm trying to extract metadata. I am doing this using tshark, opening the file, extracting a couple dozen fields, then writing the table to disk. I've noticed that this process can be pretty time consuming, sometimes up to 60 minutes for a single PCAP file. I am performing reverse DNS on the data, using the default settings (-N dmN) and I have the same reverse DNS settings in Wireshark. I understand that reverse DNS is a fairly time-consuming process relative to other processes that tshark/Wireshark is performing. However, when opening the same file in Wireshark and in tshark, Wireshark loads the file in a matter of seconds, while tshark will take minutes. My tshark command is:

tshark -r my_pcap_file.pcap \
    -2 \
    -T fields \
    -E separator=/t \
    -E header=y \
    -E quote=d \
    -e frame.time_epoch \
    -e frame.len \
    -e frame.protocols \
    -e _ws.malformed \
    -e _ws.col.Protocol \
    -e _ws.col.Length \
    -e ip.rec_rt \
    -e ip.src \
    -e ip.dst \
    -e ip.src_host \
    -e ip.dst_host > my_pcap_file.tsv

I've timed the processing of a few files using /usr/bin/time followed by the tshark command shown above. To measure the fastest possible time, neglecting writing the output to disk, I directed the output to /dev/null instead of my_pcap_file.tsv. The resulting file sizes and timing outputs are:

20.7 MB: 6.16 user 3.51 system 11:36.95 elapsed 1% CPU

10.2 MB: 2.18 user 3.28 system 10:45.22 elapsed 0% CPU

42.1 MB: 6.70 user 5.13 system 44:07.60 elapsed 0% CPU

Is there a known reason for this speed difference? More importantly, is there a way I can speed up the tshark processing?