Lockstat Command Output – Locks by Resource
The “Locks by resource” portion of lockstat groups the individual locks by resource block and shows any contention that can lead to query performance problems.
Here is sample output from this section:
---------------------------Locks by resource-----------------------
Id: 00000020 Gr: IS Conv: IS Cbacks 0 Value: <0000000000000002>
KEY(SV_PAGE,DB=00000001,TABLE=[1,0],PAGE=3)
Id: 0000000A Llb: 0000000B Gr: IS Req: IS State: GR PHYS(1)
Id: 00000021 Gr: IS Conv: IS Cbacks 0 Value: <0000000000000000>
KEY(SV_PAGE,DB=00000001,TABLE=[1,0],PAGE=30)
Id: 0000000B Llb: 0000000B Gr: IS Req: IS State: GR PHYS(1)
Id: 00000022 Gr: IS Conv: IS Cbacks 0 Value: <0000000000000000>
KEY(SV_PAGE,DB=00000001,TABLE=[1,0],PAGE=2)
Id: 0000000C Llb: 0000000B Gr: IS Req: IS State: GR PHYS(1)
Id: 00000023 Gr: IS Conv: IS Cbacks 0 Value: <0000000000000000>
KEY(SV_PAGE,DB=00000001,TABLE=[1,0],PAGE=23)
Id: 0000000D Llb: 0000000B Gr: IS Req: IS State: GR PHYS(1)
Id: 00000024 Gr: IS Conv: IS Cbacks 0 Value: <0000000000000000>
KEY(SV_PAGE,DB=00000001,TABLE=[1,0],PAGE=1)
Id: 0000000E Llb: 0000000B Gr: IS Req: IS State: GR PHYS(1)
Id: 00000025 Gr: IS Conv: IS Cbacks 0 Value: <0000000000000000>
KEY(SV_PAGE,DB=00000001,TABLE=[1,0],PAGE=33)
Id: 0000000F Llb: 0000000B Gr: IS Req: IS State: GR PHYS(1)
Fields are as follows:
Id
Internal Resource block identifier
Gr
Granted mode of the resource
Cbacks
Number of resource locks that contain DMCM callback information. This field is relevant only when the installation has been configured to run with the Distributed Multi-Cache Management (DMCM) protocol.
Conv
Conversion mode requested on the resource
Value
Lock value associated with the resource
KEY
Byte string identifying the resource
The indented portions of the resource blocks show the individual lock blocks that are contending for the resource. These lock blocks are described as follows:
Id
Internal Lock block identifier
Llb
Lock list identifier on which this lock resides
Gr
Granted mode of the lock
Req
Requested lock mode
State
Current state of the lock: GR is granted; WT is waiting
Last modified date: 08/28/2024