We put tremendous effort to build a plugin that can play nice with as many website hosting providers as possible. However, that can’t happen as are thousands of different hosts, so are the divergent hosting parameters unique to each one of them.
The Advanced Settings section of the plugin is built to help users customize the parameters of the backups to the limits of their web hosts.
If you encounter an error when backing up, restoring or migrating your website, try to modify these parameters, this increases the chances for a successful backup.
What Are The Advanced Settings and How to Use Them?
Before we start, we’d like to explain what is disk I/O on a web server and what’s the relationship between disk I/O rate and PHP script execution timeout.
Disk I/O is an important performance metric for web servers; it indicates how many input/output operations can be performed per second on a server disk. For example, assuming that the disk I/O on your web server is 1MB/s, your website is 300MB, then if the maximum PHP script execution time on your server is less than 300s, every single backup/migration/restoration mission performed to the site may fail as the PHP script can be killed by the webserver. Many web hosting providers even some famous ones have set a limit to the disk I/O on their web servers to save server resources, but some web hosting providers are not limiting. Typically, there are two ways for you to check the disk I/O on your web server:
- Ask your web host
- Check it through cPanel
Despite the disk IO is completely uncontrollable on our side, we still try to increase the backup/migration/restoration success rate by providing these advanced settings on our plugin.
Learning Mode
Optimized for resource-limited servers, this option helps improve backup/migration success rates. Note that the backup time may be longer when enabled.
Auto Delete Backup Logs
When enabled, this option will automatically delete the backup logs upon the deletion of the corresponding backup.
Large Database Mode
This mode optimizes the backup process for high-volume data. You can enable it if backups are failing or timing out because of a very large database.
Large Uploads Mode
This mode improves backup performance, especially for extensive media libraries. You should enable it if backups are slow or fail due to a large number of files in the uploads folder. Note: This mode only supports ZipArchive and is incompatible with PclZip.
Database access method:
1. WPDB
The WPDB option offers better compatibility, but the speed of backup and restore operations is slower.
2. PDO
If the pdo_mysql extension is installed on your server, we recommend choosing the PDO option, as it allows for faster site backup and restoration.
Backup compression method
1. ZipArchive
ZipArchive offers greater flexibility, resulting in a higher backup success rate and speed. It is the default ZIP method used by WPvivid Pro. Using this method requires the ZIP extension to be installed in your PHP environment.
2. PclZip
PclZip is a stable, yet slower, ZIP method that comes included with every WordPress installation. WPvivid will automatically revert to using PclZip if the necessary ZIP extension is not installed in your PHP environment.
Backup performance mode
1. Low (Balanced)
Use this default setting to minimize server resource usage. This option is best for shared hosting or environments with limited resources. Expect longer backup times, as backups are split into 200MB chunks.
2. Mid (Standard)
This mode offers an excellent balance between backup speed and server resource usage, making it suitable for most web hosting environments.
3. High (Accelerated)
This mode uses more server resources to significantly reduce backup time, but it is only recommended for dedicated servers. If you experience backups timing out or getting stuck, switch to Mid or Low mode. Backups are processed in 4GB chunks.
4. Custom (Advanced)
This mode enables fine-tuning of backup parameters. Caution: Incorrect configuration can easily lead to backup failures. It is strongly recommended to use this setting only with specific guidance from our support team.
If the backup/migration fails again, this shows your server resources are critically insufficient, then you should consider adjusting following advanced settings in Custom section
The number of files compressed to the backup zip each time
This value defines the number of files the plugin compresses into the backup ZIP file during each step of the backup process. The default value is 500. Note that a lower value increases the backup success rate but also lengthens the backup time. If you experience a backup timeout issue, try decreasing this value.
Split a backup every this size
Some web hosting providers limit the size of ZIP files (e.g., 200MB). For large websites, splitting your backup into multiple parts is an ideal way to avoid hitting this limitation. If you encounter backup errors, try adjusting this value. Note that setting the value to 0MB will automatically split backups every 4GB.
Why Splitting is Necessary
This option allows the backup task to be split into smaller segments. For instance, if your server’s PHP execution time is 120 seconds and disk I/O is 1MB/s, the theoretical maximum website size you can back up in a single task is 120MB. If your site is larger (e.g., 1GB), you can configure this option to compress files every 100MB, effectively splitting the entire backup into ten smaller tasks.
Hosting Limitations
Splitting your backup into multiple parts is also an ideal way to avoid restrictions imposed by some web hosting providers who limit the size of large ZIP files (e.g., 200MB).
Troubleshooting
If you encounter the error: “Backup error: Too many resumption attempts,” try decreasing this value to a lower setting, such as 100MB. This modification can significantly increase the success rate of backups and migrations. Do not set this option lower than 50MB.
The number of database tables compressed to each zip
This value defines the number of database tables the plugin compresses into the backup ZIP file during each step of the process. The default value is 1000, which is suitable for most websites.
Split a sql file every this size
Some web hosting providers limit the size of large SQL files. Splitting your SQL files into multiple parts is an ideal way to avoid hitting this limitation. The default value is 400, and we do not recommend setting the value lower than 100. If you encounter a backup timeout error, try adjusting this value.
Exclude files larger than this size
Enabling this option will exclude files larger than the specified size (in MB) from the backup process. Setting the value to 0 (zero) means there is no size limit, and all files will be included.
Large files can cause backup or migration failures. You can use this option to exclude unnecessary large files—such as videos and media—from the backup.
Maximum PHP script execution time for a backup/migration task
This timeout is internal to the plugin and is separate from your server’s PHP timeout settings. If the execution time is exhausted, the plugin will shut down the backup process. A timeout usually indicates a medium or large-sized website; in this case, please try increasing this value.
The default value is 1800s, which is sufficient for a shared hosting account.
If a backup or migration fails due to exceeding the maximum PHP script execution time on a VPS or dedicated server, try setting a larger value, but do not exceed 3600 seconds.
Maximum PHP memory for a backup task
This value sets a temporary PHP memory limit specifically for the WPvivid backup task. The default setting is 256M. If you encounter a “memory exhausted” error, increase this value. Note that some web hosting providers may not support this adjustment.
Utility: This option is especially useful for backing up or migrating databases that contain many tables or tables with a high row count (e.g., a table with 500,000 rows).
Default Function: Once enabled, the plugin automatically applies a temporary PHP memory limit to run the task. By default, this value is set to 256MB (recommended by official WordPress) and is released automatically once the backup or migration is complete.
Troubleshooting: If you encounter a backup or migration failure, you should modify this value to 512MB or higher, depending on the size of your database.
Note: The option will not work if the value you enter is not adequate for running of a task, then you’ll still get errors like: [error]type: 1, Allowed memory size of 268435456 bytes exhausted (tried to allocate 20480 bytes) file:/home/subhwynw/public_html/wp-admin/includes/class-pclzip.php line:5492. In that case, please try to increase the value and try again.
Chunk size
Some web hosts impose a limit on the size of data packages processed on their servers (often 2MB), which restricts the maximum transfer rate. If you experience a failure when migrating a website or backing up to remote storage, lower this value to 512KB or 256KB to prevent exceeding the limit.
For example, if you set a chunk size of 2MB, an 8MB file will be split into 4 chunks. Decreasing this chunk size value is used to bypass your Internet Service Provider’s (ISP’s) transmission limits, such as a 512KB file size limit.