still having this problem.
I just started a backup (client side) for a User.
Running top I get repquota for some minutes and then
16311 nobody 20 0 53024 16592 2644 R 100.0 0.0 8:21.54 directadmin
# lsof -p 16311
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
directadm 16311 nobody cwd DIR 9,2 4096 93194993 /usr/local/directadmin
directadm 16311 nobody rtd DIR 9,2 4096 2 /
directadm 16311 nobody txt REG 9,2 8809304 93195240 /usr/local/directadmin/directadmin
directadm 16311 nobody mem REG 9,2 555888 93195460 /usr/lib64/libfreeblpriv3.so
directadm 16311 nobody mem REG 9,2 61624 93194453 /usr/lib64/libnss_files-2.17.so
directadm 16311 nobody mem REG 9,2 11392 93192968 /usr/lib64/libfreebl3.so
directadm 16311 nobody mem REG 9,2 2156160 93194067 /usr/lib64/libc-2.17.so
directadm 16311 nobody mem REG 9,2 88776 93195467 /usr/lib64/libgcc_s-4.8.5-20150702.so.1
directadm 16311 nobody mem REG 9,2 1137024 93194370 /usr/lib64/libm-2.17.so
directadm 16311 nobody mem REG 9,2 991616 93194043 /usr/lib64/libstdc++.so.6.0.19
directadm 16311 nobody mem REG 9,2 43776 93194456 /usr/lib64/librt-2.17.so
directadm 16311 nobody mem REG 9,2 142232 93194333 /usr/lib64/libpthread-2.17.so
directadm 16311 nobody mem REG 9,2 105824 93194455 /usr/lib64/libresolv-2.17.so
directadm 16311 nobody mem REG 9,2 19288 93194348 /usr/lib64/libdl-2.17.so
directadm 16311 nobody mem REG 9,2 90248 93194218 /usr/lib64/libz.so.1.2.7
directadm 16311 nobody mem REG 9,2 40664 93194246 /usr/lib64/libcrypt-2.17.so
directadm 16311 nobody mem REG 9,2 163400 93192764 /usr/lib64/ld-2.17.so
directadm 16311 nobody 0r CHR 1,3 0t0 1028 /dev/null
directadm 16311 nobody 1u CHR 1,3 0t0 1028 /dev/null
directadm 16311 nobody 2u CHR 1,3 0t0 1028 /dev/null
directadm 16311 nobody 3r REG 9,3 20389908 142868483 /home/tmp/quota-dump.tHqhnW7aZONDBhzk5NharUkCXmQfQkVH1Lyns6NRSledQdOVz33qVl20YQdwB8DA.greotleb
directadm 16311 nobody 4u IPv6 17120929 0t0 TCP lnx8.ormag.net:EtherNet/IP-1->host228-252-dynamic.233-95-r.retail.telecomitalia.it:56379 (ESTABLISHED)