Today I saw massive blocking in one of my production database instance. On looking further I found that some of the transactions being blocked by SPID-4. I was totally clueless.
I know SPID -2 related to orphaned DTC and -3 is deferred transaction. I have never before heard of or seen -4 SPID.
I would like to know if anybody has seen this before or what may have caused this.
Thanks for your help in advance.