Patent ID: 8239588

Claim:
An I/O node control system, comprising: a file system storing data; I/O nodes on which I/O threads are run to access said file system; compute nodes which execute jobs and issue an I/O request which requests an access to said file system by using I/O threads when an I/O operation occurs in said jobs; and a job server which provides job scheduling and dynamically determines, for a certain job, a number of allocated ones of said I/O nodes and allocated I/O node occupation ratios which are ratios of job maximum I/O thread numbers, which are numbers of I/O threads allowed to be occupied by the job, to I/O node maximum I/O thread numbers, which are maximum numbers of I/O threads allowed to be generated in the allocated I/O nodes without stopping execution of the job, wherein said job server includes an I/O node scheduler which, when being not able to fully secure a corresponding number of I/O threads to said I/O node occupation ratios requested by a job upon start of the job, allows the job to occupy a number of I/O threads of said I/O nodes so as to satisfy an I/O node occupation ratio reduced down to a securable value.