6. An apparatus of ordering search results, comprising: one or more processors; memory; an acquisition module stored in the memory and executable by the one or more processors that is configured to obtain exposed log files from a log system; a probability computation module stored in the memory and executable by the one or more processors that is configured to compute Bayesian posterior probabilities of relevancy between the exposed log files and a search request; an expected value computation module stored in the memory and executable by the one or more processors that is configured to compute expected values of the relevancy between the exposed log files and the search request based on the Bayesian posterior probabilities; an indexing module stored in the memory and executable by the one or more processors that is configured to store the search request and identifiers of the exposed log files as keys and the expected values of the relevancy between the exposed log files and the search request as respective values into a search data structure; a search module stored in the memory and executable by the one or more processors that is configured to find expected values of relevancy between a search request submitted by a user and log files that are relevant to the submitted search request from the search data structure in response to receiving the search request submitted by the user; an ordering module stored in the memory and executable by the one or more processors that is configured to order the found log files according to a descending order of the found expected values; and a first filtering module configured to filter the exposed log files based on global parameters prior to computing the expected values of the relevancy between the exposed log files and the search request based on the Bayesian posterior probabilities, wherein a log file having a global parameter less than a corresponding predefined threshold is filtered, and wherein the expected value computation module is further configured to compute the expected values of the relevancy between the filtered log files and the search request based on the Bayesian posterior probabilities.
6. An apparatus of ordering search results, comprising: one or more processors; memory; an acquisition module stored in the memory and executable by the one or more processors that is configured to obtain exposed log files from a log system; a probability computation module stored in the memory and executable by the one or more processors that is configured to compute Bayesian posterior probabilities of relevancy between the exposed log files and a search request; an expected value computation module stored in the memory and executable by the one or more processors that is configured to compute expected values of the relevancy between the exposed log files and the search request based on the Bayesian posterior probabilities; an indexing module stored in the memory and executable by the one or more processors that is configured to store the search request and identifiers of the exposed log files as keys and the expected values of the relevancy between the exposed log files and the search request as respective values into a search data structure; a search module stored in the memory and executable by the one or more processors that is configured to find expected values of relevancy between a search request submitted by a user and log files that are relevant to the submitted search request from the search data structure in response to receiving the search request submitted by the user; an ordering module stored in the memory and executable by the one or more processors that is configured to order the found log files according to a descending order of the found expected values; and a first filtering module configured to filter the exposed log files based on global parameters prior to computing the expected values of the relevancy between the exposed log files and the search request based on the Bayesian posterior probabilities, wherein a log file having a global parameter less than a corresponding predefined threshold is filtered, and wherein the expected value computation module is further configured to compute the expected values of the relevancy between the filtered log files and the search request based on the Bayesian posterior probabilities. 11. The apparatus as recited in claim 6 , wherein the indexing module employs a trie tree to store the search request and the identifiers of the exposed log files as the keys and the expected values of the relevancy between the exposed log files and the search request as respective values into the search data structure.