memc_buffer_size
The `memc_buffer_size` directive defines the size of the buffer used for data received from the memcached server.
Description
The memc_buffer_size directive is part of the ngx_memc module, which provides extended capabilities for interacting with Memcached. This directive specifies the maximum size of the buffer allocated for receiving data from the Memcached server after a request is made. When a client sends a request to retrieve or manipulate data stored in Memcached, the server responds with the requested data, and this data is buffered by NGINX based on the size defined in memc_buffer_size.
This directive is particularly useful in scenarios where large amounts of data are being fetched from Memcached, allowing the server to better handle large payloads without running into memory allocation issues. Properly sizing the buffer ensures that responses do not exceed the defined limit, which could lead to data truncation or service interruptions. Adjusting this value can optimize performance for applications that frequently access large data sets from Memcached.
The buffer size is set within the context of the http, server, or location blocks and accepts a single argument, typically expressed in bytes, with suffixes such as K, M, or G for kilobytes, megabytes, or gigabytes, respectively. The value must be a valid, positive integer that defines the total size of the buffer used when interacting with Memcached servers.
Config Example
location /foo {
set $memc_key $arg_key;
memc_buffer_size 2m;
memc_pass 127.0.0.1:11211;
}Setting the buffer size too low may lead to incomplete data being read from Memcached, especially for larger objects.
Not adjusting this value appropriately can impact performance, as NGINX might need to perform additional memory allocations if the buffer is exceeded.