New Relic
imgproxy can send its metrics to New Relic. To use this feature, do the following:
- Register at New Relic and get a license key.
 - Set the 
IMGPROXY_NEW_RELIC_KEYenvironment variable to the license key. - (optional) Set the 
IMGPROXY_NEW_RELIC_APP_NAMEenvironment variable to be the desired application name. - (optional) Set the 
IMGPROXY_NEW_RELIC_LABELSenvironment variable to be the desired list of labels. Example:label1=value1;label2=value2. 
imgproxy will send the following info to New Relic:
- CPU and memory usage
 - Response time
 - Queue time
 - Image downloading time
 - Image processing time
 - Errors that occurred while downloading and processing an image
 
Additionally, imgproxy sends the following metrics over Metrics API:
imgproxy.requests_in_progress: the number of requests currently in progressimgproxy.images_in_progress: the number of images currently in progressimgproxy.buffer.size: a summary of the download buffers sizes (in bytes)imgproxy.buffer.default_size: calibrated default buffer size (in bytes)imgproxy.buffer.max_size: calibrated maximum buffer size (in bytes)imgproxy.vips.memory: libvips memory usage (in bytes)imgproxy.vips.max_memory: libvips maximum memory usage (in bytes)imgproxy.vips.allocs: the number of active vips allocations