G
George Potemkin
Guest
Thank you, Gus. > note that user -1 is an indication that no one is holding the buffer lock. so is use count 0. From "The Secret Life of Latches" presentation: Session run: REPEAT: FIND FIRST Customer NO-LOCK. END. I did: kill -SIGSTOP -> promon/ Buffer Lock Queue -> kill -SIGCONT After a few tries (a ten or so) I caught the session with a buffer locked: 10/02/16 Status: Buffer Lock Queue by user number for all tenants Usr:Ten DBKEY Area T Status Type Usect -1 384 8 D LOCKED SHARE 1 But the another menu in promon was still showing who is locking the buffer: 10/02/16 Status: Buffer Locks by user number for all tenants User:Ten DBKEY Area Hash T S Usect 1 6 384 8 221 D S 1 The session was frozen so the data were not changing. I know that information about buffer locks is stored in two different places: 1) In buffer headers (-B + -B2 + 2) scanned by "Status: Buffer Lock Queue"; 2) In Usrctl table (-n + -Mn + 2) scanned by "Status: Buffer Locks". Is it correct to say that the chains in the buffer headers is a real buffer lock "table" while data in Usrctl table is just a replica?
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