Performance improvement of web pages by on-demand generation of composite images

A server system comprising:

• one or more processors;
• memory;
• and
• one or more programs stored in the memory, the one or more programs comprising instructions that, in response to being executed by the one or more processors, cause the server system to perform operations comprising:
• receiving a request for a first webpage from a first client system via a network;
• identifying a first list of one or more images referenced by the requested first webpage;
• determining whether there is a chance of network latency problems related to the first client system loading the requested webpage based on a preexisting latency issue that already exists and based on information about at least one of a size, a type, a number, or a location of a first set of images;
• in response to determining that the chance of network latency problems related to the first client system loading the requested webpage exceeds a threshold amount, determining, based on one or more image display factors corresponding to the first webpage, a second list of one or more images referenced by the first webpage, the second list of one or more images being a subset of the first list of one or more images;
• determining whether the second list of one or more images referenced in the first webpage matches a list of images referenced by a composite image file stored in a database of composite images;
• and
• in response to determining that the second list of one or more images referenced by the requested first webpage matches the list of images by the composite image file, retrieving the composite image file and transmitting the composite image file to the first client system, wherein the composite image file includes data describing corresponding image locations, within the first webpage, of each image of the second list of one or more images referenced by the composite image file.

A non-transitory computer-readable storage medium storing instructions that, in response to being executed by one or more processors of a machine, cause the machine to perform operations comprising:

• receiving a request for a first webpage from a first client system via a network;
• identifying a first set of images referenced by the first webpage;
• determining whether there is a chance of network latency problems related to the first client system loading the requested webpage based on a preexisting latency issue that already exists and based on information about at least one of a size, a type, a number, or a location of the first set of images;
• in response to determining that the chance of network latency problems related to the first client system loading the requested webpage exceeds a threshold amount, determining, based on one or more image display factors corresponding to the first webpage, a second set of images referenced by the first webpage, the second set of images being a subset of the first set of images;
• generating a first file that includes data describing corresponding image locations, within the first webpage, of each image of the second set of images;
• and
• transmitting the first file to the first client system, the transmitting causing the first client system to display the second set of images according to the first file.