Optimize JuiceFS performance settings and mount options

The changes tune TCP buffers and enhance JuiceFS mount options for
better throughput and caching behavior.

config/ansible/templates/juicefs.service.j2

@@ -5,7 +5,19 @@ Before=docker.service
 
 [Service]
 Type=simple
-ExecStart=/usr/local/bin/juicefs mount redis://:{{ redis_password }}@localhost:6379/0 /mnt/object_storage --cache-dir=/var/jfsCache --buffer-size=1024 --prefetch=4 --cache-size=131072 --attr-cache=3 --entry-cache=3 --open-cache=3
+ExecStart=/usr/local/bin/juicefs mount redis://:{{ redis_password }}@localhost:6379/0 /mnt/object_storage \
+  --cache-dir=/var/jfsCache \
+  --buffer-size=4096 \
+  --prefetch=16 \
+  --cache-size=131072 \
+  --attr-cache=4 \
+  --entry-cache=4 \
+  --open-cache=4 \
+  -o writeback_cache \
+  --max-uploads=80 \
+  --max-deletes=80 \
+  --writeback \
+  --upload-delay=30s
 Restart=on-failure
 
 [Install]