Current article covers the settings of today's latest Sync version. Older Sync versions may be missing some settings or still have deprecated ones.
To open Power user preferences, click Options (the cog button) > Preferences > Advanced > Open power user preferences:
Sync power user preferences:
| Name | Default value | Purpose |
| share_file_ttl | 3 | Number of days that single file share is valid. Max value is 7. |
| send_statistics | true | Allows Sync to send anonymous statistical metrics. It only collects data like OS and Sync version, whether Sync is active or not, etc. Resilio never collects any private or sensitive info! |
| disable_remove_from_all_devices | false | If enabled, the context menu item "Remove from all devices" will be unavailable for Selective Sync shares. Ignored in Linux WebUI. |
| peer_expiration_days | 7 (day) | Number of days to pass before a peer is removed from the peer list |
| log_size | 100 (MB) | Amount of memory allocated for debug logs |
| free_space_warning_threashold | 1024 (MB) | If that much space is left on drive with default folder location, Sync will give a warning and stop syncing files |
| log_ttl | 7 (day) | Amount of time debug logs will be stored |
| profiler_enabled | false | Starts recording data for speed issue analysis. Data is stored in profiler.dat in storage folder, rotated every 10 minutes. Requires client restart to activate. |
| config_refresh_interval | 3600 (sec) | Controls how often Sync checks for the info about available trackers and relay servers. Can be adjusted to prevent HDD from low-power mode |
| config_save_interval | 600 (sec) | Controls how often settings are saved to storage. Can be adjusted to prevent HDD from low-power mode |
| disk_low_priority | false | Forces all disk read-write operations to low priority |
| disk_worker_per_job | false | If set to true, each share will have standalone drive thread and won't be affected by other shares, especially by rescans |
| prefer_net_over_disk_operations | false | If enabled, Sync won't count files' difference, but will re-download the file instead |
| worker_threads_count | 0 | Number of CPU threads to use during indexing. "0" means "use as many threads as possible on all cores available". 1 means one thread only, and so on. *** |
| show_service_disk_thread | false | Shows or hides disk threads in overview graphs |
| enable_warning_no_source | true | Shows warning about peer that has requested file is not connected to the share. |
| use_advapi_crypto | false | If enabled, Sync will be using advapi32 library instead of bcrypt. |
| net_enable_utp2 | true | Enables WAN optimization. Works only if WAN feature is present in license (for legacy licenses) |
| rate_limit_local_peers | false | Limits LAN bandwidth |
| bind_interface |
not set (eth0, wlan0, etc or MAC address) |
Specifies network interface which will be used by Sync ** |
| use_only_bind_interface |
false |
If enabled, Sync won't attempt to connect to other peers unless interface from "bind_interface" option is available. |
| external_port | 0 | External (i.e. relative to NAT) port value |
| max_packet_size | 32 (Mb) | Maximum allowed packet size containing sync service data (tree nodes, ACLs, etc.) |
| max_torrent_metadata_size | 16 (MB) | Amount of memory allocated for metadata |
| max_file_size_for_versioning | 1000 (MB) | Defines the maximum size of file that will keep its old versions in Archive |
| folder_rescan_interval | 600 (sec) | Every folder_rescan_interval Sync rescans folder for changes it could miss with other means |
| sync_max_time_diff | 600 (sec) | Maximum time difference allowed between peers. If the actual time difference exceeds this value, Sync won't transfer data and will display an error |
| ignore_mtime_assign_errors | false | If set to true, and Sync fails to write files' mtime on disk, Sync will stop trying and keep the correct mtime on database only. Note: mtime on disk will be 'current' timestamp! |
| sync_trash_ttl | 30 (day) | Amount of time a file will be stored in the archive |
| tunnel_compress_stream |
false | Works only in Sync Business. If enabled, Sync will compress transferred data and save traffic. Side effect will be slower sync speed and higher CPU usage due to necessity to decompress. Shall be enabled on both sender as receiver so as to take effect. |
| tunnel_compress_delay_size | 102400 | Delay for uploading compressed data. Until defined size is collected, files won't be uploaded. |
| tunnel_compress_delay_time | 10000 | in microseconds. Delay for uploading compressed data. |
| tunnel_protocols |
utp;utp2; |
Forces peer to use this or that protocol. Note, for peers to connect they shall have some common protocols configured. |
| tunnel_ciphers |
SYNC-SRP;DHE-PSK-AES128-GCM-SHA256;DHE-PSK-AES256-GCM-SHA384 |
TLS ciphers to be used by peers. For peers to connect some |
| torrent_max_piece_size | 2097152 | Deprecated. in bytes. Decrease pieсe size to reduce delta diff when syncing. Downside might be reduced speed and higher CPU usage |
| torrent_piece_size_policy | 0 | Deprecated. Possible value is 1. Set "1" to make it equal to sqrt(file_size). |
| prefer_utp2_lan | false | Enabled WAN optimization in LAN as well. |
| lan_encrypt_data | true | Forces to encrypt all Sync data flowing in LAN |
| transfer_job_verify_downloaded_files | false | Forces peer to recalculate file hash again after writing to disk. Works for file send option. Enabling it may cause excessive disk load operations. |
| transfer_job_skip_locked_files | false |
Deprecated. Applies to sharing single file feature. Locked files will be skipped. |
| ignore_symlinks | false | Ignores symbolic links and does not sync them |
| folder_defaults.use_tracker | true | Enables/disables the use of tracker |
| folder_defaults.use_lan_broadcast | true | Deprecated. Enables/disables LAN broadcast |
| folder_defaults.lan_discovery_mode | 3 | Replaces "folder_defaults.use_lan_broadcast". 0 - "Disabled", 1 - "Multicast only", 2 - "Broadcast only", 3 - "Enabled (both)" |
| folder_defaults.use_relay | true | Enables/disables the use of relay |
| folder_defaults.delete_unknown_files | false | |
| sync_ro_delete_unknown_file | false | Works for Sync jobs, for empty folder on RO agent. Not optimized for pre-seeded folders |
| overwrite_changes | false | Enables "Overwrite any changed files" for Read-only shares by default |
| folder_defaults.known_hosts | not set | Hosts should be entered as a single line of IP:port pairs (or DNSname:port pairs*) comma-separated (no other delimiters allowed) |
| lazy_indexing | true | Works only in Sync Business. If enabled, Sync won't calculate hash of file until remote peer requests it. Note: renaming placeholder on remote peer won't work, file will not be renamed accordingly on source peer. |
| direct_torrent_enabled | true | If file is smaller than current speed, it won't be broken into pieces. This may reduce transfer time as fewer requests are made and fewer pieces are transferred, but if transfer is interrupted, file will be re-synced from start. |
| direct_torrent_mem_limit | 536870912 | In bytes. Memory allocated for direct torrents. |
| prioritize_initial_indexing | true | Applies only to initial rescan on pre-seeded folders. When enabled, files won't be syncing until peers rescan their folders -- good for huge folders with millions of files so that they're indexed quickly |
| sync_extended_attributes | true | Disables or enabled syncing of xattrs and streams |
| fix_conflicting_paths | true | If disabled, Sync won't set Conflicts for conflicting filenames and if there's indeed a conflicting file name, share won't get synced. Disabling it may have unpredictable results. |
| net.udp_ipv4_mtu | 1500 | Sets MTU size for IPv4 network |
| net.udp_ipv6_mtu | 1500 | Sets MTU size for IPv6 network |
| disk_min_free_space | 0 (%) | Options to reserve space on disk. Is an offset to free_space_warning_threashold |
| disk_worker_pool_size | 1 | Number of threads each disk uses for disk operations. This shall improve performance on high-latency CIFS with multiple worker threads support. Applicable for high speed drives (fast ssd, raid). May be used to find best performance on network shares |
| disk_min_free_space_gb | 0 (GB) | Options to reserve space on disk. Is an offset to free_space_warning_threashold |
| parallel_indexing | false | If enabled, all shares will be rescanned at the same time. This may cause heavy disk and CPU usage. |
| enable_file_system_notifications | true | Enables/disables operating system notifications about file update |
| keep_expired_transfer_days | 0 | Number of days that Sync keeps expired file transfer in UI. |
| keep_expired_transfer_num | 100 | Number of files send transfers that Sync will keep in UI |
| normalize_unicode_paths | true | Normalizing unicode in filenames (making it in composed/decomposed form). |
| recheck_locked_files_interval | 600 | If Sync encounters a file which is locked by another app, it will recheck file's availability later. Too frequent recheck on large number of locked files may cause high CPU usage. |
| recreate_placeholders_on_removal | false | Used in Selective Sync shares. If enabled, user won't be able to delete a placeholder and thus propagate deletion to other peers. |
| tracker_protocols | utp;tcp | Protocols used to connect to tracker server. |
* DNS name is resolved by OS means once per minute.
**The value is operating system-dependent. Correct syntax for MAC addresses is using lower case and colons: b8:27:eb:d2:00:3c, for example. If the defined interface is not available, Sync will switch to next active interface.
*** Sync still has some number of working threads created for ongoing work - disk jobs, connections, working with UI. This value sets the number of additional threads for other tasks, like indexing, checking file signatures, etc It's advisable not to use too many threads on slow CPU so as to avoid its overloading.