Refactor memcached

[ervin09]

Had issues with the current version code of LibreNMS, it throws out error in handling JSON.

This was my full error trace:

<<<app-memcached>>> {"localhost:11211":{"pid":3752269,"uptime":2594,"time":1786974518,"version":"1.5.22","libevent":"2.1.8-stable","pointer_size":64,"rusage_user":0.33320699999999998,"rusage_system":1.1369279999999999,"max_connections":1024,"curr_connections":9,"total_connections":1968,"rejected_connections":0,"connection_structures":59,"reserved_fds":20,"cmd_get":872,"cmd_set":3699,"cmd_flush":1,"cmd_touch":309,"cmd_meta":0,"get_hits":803,"get_misses":69,"get_expired":0,"get_flushed":0,"delete_misses":2,"delete_hits":865,"incr_misses":0,"incr_hits":0,"decr_misses":0,"decr_hits":0,"cas_misses":0,"cas_hits":0,"cas_badval":0,"touch_hits":309,"touch_misses":0,"auth_cmds":0,"auth_errors":0,"bytes_read":1007079,"bytes_written":2822312,"limit_maxbytes":67108864,"accepting_conns":1,"listen_disabled_num":0,"time_in_listen_disabled_us":0,"threads":4,"conn_yields":0,"hash_power_level":16,"hash_bytes":524288,"hash_is_expanding":0,"slab_reassign_rescues":0,"slab_reassign_chunk_rescues":0,"slab_reassign_evictions_nomem":0,"slab_reassign_inline_reclaim":0,"slab_reassign_busy_items":0,"slab_reassign_busy_deletes":0,"slab_reassign_running":0,"slabs_moved":0,"lru_crawler_running":0,"lru_crawler_starts":2295,"lru_maintainer_juggles":10988,"malloc_fails":0,"log_worker_dropped":0,"log_worker_written":0,"log_watcher_skipped":0,"log_watcher_sent":0,"bytes":230611,"curr_items":255,"total_items":1627,"slab_global_page_pool":0,"expired_unfetched":18,"evicted_unfetched":0,"evicted_active":0,"evictions":0,"reclaimed":19,"crawler_reclaimed":0,"crawler_items_checked":18,"lrutail_reflocked":12,"moves_to_cold":1123,"moves_to_warm":226,"moves_within_lru":138,"direct_reclaims":0,"lru_bumps_dropped":0}} Output post stripslashes: <<<app-memcached>>> {"localhost:11211":{"pid":3752269,"uptime":2594,"time":1786974518,"version":"1.5.22","libevent":"2.1.8-stable","pointer_size":64,"rusage_user":0.33320699999999998,"rusage_system":1.1369279999999999,"max_connections":1024,"curr_connections":9,"total_connections":1968,"rejected_connections":0,"connection_structures":59,"reserved_fds":20,"cmd_get":872,"cmd_set":3699,"cmd_flush":1,"cmd_touch":309,"cmd_meta":0,"get_hits":803,"get_misses":69,"get_expired":0,"get_flushed":0,"delete_misses":2,"delete_hits":865,"incr_misses":0,"incr_hits":0,"decr_misses":0,"decr_hits":0,"cas_misses":0,"cas_hits":0,"cas_badval":0,"touch_hits":309,"touch_misses":0,"auth_cmds":0,"auth_errors":0,"bytes_read":1007079,"bytes_written":2822312,"limit_maxbytes":67108864,"accepting_conns":1,"listen_disabled_num":0,"time_in_listen_disabled_us":0,"threads":4,"conn_yields":0,"hash_power_level":16,"hash_bytes":524288,"hash_is_expanding":0,"slab_reassign_rescues":0,"slab_reassign_chunk_rescues":0,"slab_reassign_evictions_nomem":0,"slab_reassign_inline_reclaim":0,"slab_reassign_busy_items":0,"slab_reassign_busy_deletes":0,"slab_reassign_running":0,"slabs_moved":0,"lru_crawler_running":0,"lru_crawler_starts":2295,"lru_maintainer_juggles":10988,"malloc_fails":0,"log_worker_dropped":0,"log_worker_written":0,"log_watcher_skipped":0,"log_watcher_sent":0,"bytes":230611,"curr_items":255,"total_items":1627,"slab_global_page_pool":0,"expired_unfetched":18,"evicted_unfetched":0,"evicted_active":0,"evictions":0,"reclaimed":19,"crawler_reclaimed":0,"crawler_items_checked":18,"lrutail_reflocked":12,"moves_to_cold":1123,"moves_to_warm":226,"moves_within_lru":138,"direct_reclaims":0,"lru_bumps_dropped":0}} 

memcached:ERROR: -3:Invalid JSON SQL[update applications set timestamp = NOW() where app_id = ? [269] 1.04ms]


Librenms Environment:

Version | 26.8.0-dev.122+4ab87302fa - Sun Aug 16 2026 05:50:15 GMT+0200
Database Schema | 2026_07_30_162514_add_device_refresh_config_permission (397)
Web Server | nginx/1.14.1
PHP | 8.4.24
Python | 3.6.8
Database | MariaDB 11.8.8-MariaDB
Laravel | 12.64.0
RRDtool | 1.7.2
Net-SNMP | 5.8

[ervin09]

after code fix

previously all graphs had NaNN NaNN due to that error -3 in logs of librenms server, during discovery.

[bennetgallein]

code-wise this looks fine to me, but I cannot test this right now.

[ervin09]

code-wise this looks fine to me, but I cannot test this right now.

Hey man, thanks for looking into it. If you need any screenshots debug that I can provide from my side , just let me know. :)