Hum I remember something now.
You won't be able to save your 'log' variable.
The quantity of data you can send through a query string (ie: ?var=value) is limited.
The specification does not dictate a minimum or maximum URL length, but implementation varies by browser and version. For example, Internet Explorer does not support URLs that have more than 2083 characters. There is no limit on the number of parameters in a URL; only the raw (as opposed to URL encoded) character length of the URL matters. Web servers may also impose limits on the length of the query string, depending on how the URL and query string is stored. If the URL is too long, the web server fails with the 414 Request-URI Too Long HTTP status code.
The common workaround for these problems is to use POST instead of GET and store the parameters in the request body. The length limits on request bodies are typically much higher than those on URL length. For example, the limit on POST size, by default, is 2 MB on IIS 4.0 and 128 KB on IIS 5.0. the limit is configurable on Apache2 using the LimitRequestBody Directive which specifies the number of bytes from 0 (meaning unlimited) to 2147483647 (2GB) that are allowed in a request body .
And as far as I know, the Ajax object doesn't send POST request