I have a SQL Server 2008 R2 VM Server with SAN Disk Storage.
The SQL Server process is using nearly 100% with only one job running.
I had the same problem with this server last week. I got all of the user of the box and it was still consuming 100%.
Then I restarted the Service and with no active connections it quickly jumped up to 100%.
The Network Guy said that it was not as as result of the SAN this time but he was looking into an issue with the NIC.
Shortly after the CPU % dropped to normal levels.
He claimed that he did not do anything and claimed that it was the loads. Never mind that it was 100% with no users connected.
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