@Till

There are two processes running:

$ ps aux | grep cups-browsed | grep -v grep
root        2912  0.0  0.0   2892  1708 ?        Ss   10:13   0:00 /bin/sh /snap/cups/1047/scripts/run-cups-browsed
root        3407  0.0  0.0   2892   892 ?        S    10:13   0:00 /bin/sh /snap/cups/1047/scripts/run-cups-browsed

None of these relates to what top shows as culprit:

2898 root      20   0  195916  16320  11736 R 197.0   0.1 139:30.91 cupsd

$ ps -aux | grep 2898
root        2898  134  0.1 195916 16320 ?        Rsl  10:13 141:15 /usr/sbin/cupsd -l

$ sudo gbd -p 2898
(gdb) t a a bt

(gdb) t a a bt

Thread 2 (Thread 0x729b3cc006c0 (LWP 5305) "cupsd"):
#0  0x0000729b3f6a3439 in __pthread_rwlock_wrlock_full64 (abstime=0x0, clockid=0, rwlock=0x64af2f2b0270) at ./nptl/pthread_rwlock_common.c:821
#1  ___pthread_rwlock_wrlock (rwlock=0x64af2f2b0270) at ./nptl/pthread_rwlock_wrlock.c:26
#2  0x000064af2d5231a1 in create_local_bg_thread (con=0x64af2f3a1d70) at /build/cups-0ETlfZ/cups-2.4.7/scheduler/ipp.c:5333
#3  0x0000729b3f69ca94 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:447
#4  0x0000729b3f729c3c in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

Thread 1 (Thread 0x729b3e5b1b40 (LWP 2898) "cupsd"):
#0  0x0000729b3f71c5ad in __GI___libc_write (nbytes=63, buf=0x64af2f1b07c8, fd=6) at ../sysdeps/unix/sysv/linux/write.c:26
#1  __GI___libc_write (fd=6, buf=0x64af2f1b07c8, nbytes=63) at ../sysdeps/unix/sysv/linux/write.c:24
#2  0x0000729b3f95cf66 in ??? () at /lib/x86_64-linux-gnu/libcups.so.2
#3  0x0000729b3f95d3ea in cupsFileFlush () at /lib/x86_64-linux-gnu/libcups.so.2
#4  0x000064af2d5399f5 in cupsdWriteErrorLog (message=0x64af2f1ae7b0 "[Client 26] Closing connection.", level=8) at /build/cups-0ETlfZ/cups-2.4.7/scheduler/log.c:1276
#5  cupsdWriteErrorLog (level=level@entry=8, message=0x64af2f1ae7b0 "[Client 26] Closing connection.") at /build/cups-0ETlfZ/cups-2.4.7/scheduler/log.c:1220
#6  0x000064af2d539b72 in cupsdLogClient (con=<optimized out>, level=8, message=<optimized out>) at /build/cups-0ETlfZ/cups-2.4.7/scheduler/log.c:540
#7  0x000064af2d50d741 in cupsdCloseClient (con=con@entry=0x64af2f3a1d70) at /build/cups-0ETlfZ/cups-2.4.7/scheduler/client.c:405
#8  0x000064af2d50f071 in cupsdReadClient (con=0x64af2f3a1d70) at /build/cups-0ETlfZ/cups-2.4.7/scheduler/client.c:618
#9  0x000064af2d508469 in cupsdDoSelect (timeout=<optimized out>) at /build/cups-0ETlfZ/cups-2.4.7/scheduler/select.c:477
#10 main (argc=<optimized out>, argv=<optimized out>) at /build/cups-0ETlfZ/cups-2.4.7/scheduler/main.c:855

Thread 1 (process 2912 "run-cups-browse"):
#0  0x000075225bf4e7dc in sigsuspend () from target:/lib/x86_64-linux-gnu/libc.so.6
#1  0x00005d1641298ee8 in ?? ()
#2  0x00005d164129911a in ?? ()
#3  0x00005d164129e58a in ?? ()
#4  0x00005d16412a3826 in ?? ()
#5  0x00005d16412a650f in ?? ()
#6  0x00005d164129fc00 in ?? ()
#7  0x00005d16412a4b28 in ?? ()
#8  0x00005d1641297d53 in ?? ()
#9  0x000075225bf35d90 in ?? () from target:/lib/x86_64-linux-gnu/libc.so.6
#10 0x000075225bf35e40 in __libc_start_main () from target:/lib/x86_64-linux-gnu/libc.so.6
#11 0x00005d1641297f15 in ?? ()

Thread 1 (process 3407 "run-cups-browse"):
#0  0x000075225bff63ea in wait4 () from target:/lib/x86_64-linux-gnu/libc.so.6
#1  0x00005d1641298ea4 in ?? ()
#2  0x00005d164129911a in ?? ()
#3  0x00005d16412a63c0 in ?? ()
#4  0x00005d164129fc00 in ?? ()
#5  0x00005d16412a0070 in ?? ()
#6  0x00005d164129fc00 in ?? ()
#7  0x00005d16412a48ad in ?? ()
#8  0x00005d164129fc00 in ?? ()
#9  0x00005d16412a48ad in ?? ()
#10 0x00005d164129fc00 in ?? ()
#11 0x00005d164129fc3a in ?? ()
#12 0x00005d164129fc00 in ?? ()
#13 0x00005d16412a4b28 in ?? ()
#14 0x00005d1641297d53 in ?? ()
#15 0x000075225bf35d90 in ?? () from target:/lib/x86_64-linux-gnu/libc.so.6
#16 0x000075225bf35e40 in __libc_start_main () from target:/lib/x86_64-linux-gnu/libc.so.6
#17 0x00005d1641297f15 in ?? ()