I'm having this problem too!
Jan 21 10:41:37 unraid nginx: 2021/01/21 10:41:37 [alert] 13333#13333: worker process 13334 exited on signal 6
repeats about 400,000 times between 1041 and 1331, and then just numerous numerous repeats of
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [crit] 32524#32524: ngx_slab_alloc() failed: no memory
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [error] 32524#32524: shpool alloc failed
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [error] 32524#32524: nchan: Out of shared memory while allocating channel /var. Increase nchan_max_reserved_memory.
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [alert] 32524#32524: *9212036 header already sent while keepalive, client: 192.168.2.156, server: 0.0.0.0:80
Jan 21 13:31:19 unraid kernel: nginx[32524]: segfault at 0 ip 0000000000000000 sp 00007fff47105b28 error 14 in nginx[400000+21000]
Jan 21 13:31:19 unraid kernel: Code: Bad RIP value.
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [alert] 13333#13333: worker process 32524 exited on signal 11
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [crit] 32527#32527: ngx_slab_alloc() failed: no memory
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [error] 32527#32527: shpool alloc failed
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [error] 32527#32527: nchan: Out of shared memory while allocating channel /disks. Increase nchan_max_reserved_memory.
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [error] 32527#32527: *9212037 nchan: error publishing message (HTTP status code 507), client: unix:, server: , request: "POST /pub/disks?buffer_length=1 HTTP/1.1", host: "localhost"
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [crit] 32527#32527: ngx_slab_alloc() failed: no memory
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [error] 32527#32527: shpool alloc failed
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [error] 32527#32527: nchan: Out of shared memory while allocating channel /shares. Increase nchan_max_reserved_memory.
Jan 21 13:31:19 unraid nginx: 2021/01/21 13:31:19 [error] 32527#32527: *9212038 nchan: error publishing message (HTTP status code 507), client: unix:, server: , request: "POST /pub/shares?buffer_length=1 HTTP/1.1", host: "localhost"
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [crit] 32527#32527: ngx_slab_alloc() failed: no memory
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [error] 32527#32527: shpool alloc failed
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [error] 32527#32527: nchan: Out of shared memory while allocating channel /cpuload. Increase nchan_max_reserved_memory.
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [error] 32527#32527: *9212039 nchan: error publishing message (HTTP status code 507), client: unix:, server: , request: "POST /pub/cpuload?buffer_length=1 HTTP/1.1", host: "localhost"
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [crit] 32527#32527: ngx_slab_alloc() failed: no memory
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [error] 32527#32527: shpool alloc failed
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [error] 32527#32527: nchan: Out of shared memory while allocating channel /cpuload. Increase nchan_max_reserved_memory.
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [alert] 32527#32527: *9212040 header already sent while keepalive, client: 192.168.2.156, server: 0.0.0.0:80
Jan 21 13:31:20 unraid kernel: nginx[32527]: segfault at 0 ip 0000000000000000 sp 00007fff47105b28 error 14 in nginx[400000+21000]
Jan 21 13:31:20 unraid kernel: Code: Bad RIP value.
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [alert] 13333#13333: worker process 32527 exited on signal 11
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [crit] 32534#32534: ngx_slab_alloc() failed: no memory
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [error] 32534#32534: shpool alloc failed
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [error] 32534#32534: nchan: Out of shared memory while allocating channel /var. Increase nchan_max_reserved_memory.
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [alert] 32534#32534: *9212041 header already sent while keepalive, client: 192.168.2.100, server: 0.0.0.0:80
Jan 21 13:31:20 unraid kernel: nginx[32534]: segfault at 0 ip 0000000000000000 sp 00007fff47105b28 error 14 in nginx[400000+21000]
Jan 21 13:31:20 unraid kernel: Code: Bad RIP value.
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [alert] 13333#13333: worker process 32534 exited on signal 11
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [crit] 32535#32535: ngx_slab_alloc() failed: no memory
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [error] 32535#32535: shpool alloc failed
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [error] 32535#32535: nchan: Out of shared memory while allocating channel /cpuload. Increase nchan_max_reserved_memory.
Jan 21 13:31:20 unraid nginx: 2021/01/21 13:31:20 [alert] 32535#32535: *9212042 header already sent while keepalive, client: 192.168.2.100, server: 0.0.0.0:80
Jan 21 13:31:20 unraid kernel: nginx[32535]: segfault at 0 ip 0000000000000000 sp 00007fff47105b28 error 14 in nginx[400000+21000]
Jan 21 13:31:20 unraid kernel: Code: Bad RIP value.
continuing until my logs file is full.