Mutexes or wait() and signal() calls can be used to control application-managed resources (i.e. The kernel keeps track of which resources are free and which are allocated, to which process they are allocated, and a queue of processes waiting for this resource to become available for all kernel-managed resources.Some categories may only have one resource.For example, the term “printers” may need to be subdivided into “laser printers” and “color inkjet printers.” if there is some difference between the resources within a category), then that category must be subdivided further. By definition, all resources within a category are equivalent, and any of the resources within that category can equally satisfy a request from that category.Memory, printers, CPUs, open files, tape drives, CD-ROMs, and other resources are examples of resource categories.For the purposes of deadlock discussion, a system can be modeled as a collection of limited resources that can be divided into different categories and allocated to a variety of processes, each with different requirements.Software Engineering Interview Questions.Top 10 System Design Interview Questions and Answers.Top 20 Puzzles Commonly Asked During SDE Interviews.Commonly Asked Data Structure Interview Questions.Top 10 algorithms in Interview Questions.Top 20 Dynamic Programming Interview Questions.Top 20 Hashing Technique based Interview Questions.Top 50 Dynamic Programming (DP) Problems.Top 20 Greedy Algorithms Interview Questions.Top 100 DSA Interview Questions Topic-wise.Hope ESRI will understand that it is a major issue and will fix that in the new releases. It worked like a charm, no deadlocks anymore. Setting a table hint inside the procedure on both DELETE operations, that instruct to acquire a table exclusive lock on whole table, right away.Īpply the hint after the FROM clause as follows: WITH (TABLOCKX, HOLDLOCK). So when the later procedure called, it is deadlocked, on this X locks, cause it tries to get X lock on whole table, and for that it need to lock wait till other sessions release the X locks on the rows, which in turn waiting on other to do the same. this locks are held till the end of the outmost transaction. this in turn acquiring a IX lock on table, and then if it delete any row while running, it acquiring row X lock on the deleted row. (in the same transaction) that making cleanup in the table, via DELETE instruction. The problem is that before procedure runs, the calls the on the table while opening a local cursor with a table hint. We have investigated the issue deeply, and found that the deadlocks are happening when the trying to convert the IX (Intent Exclusive) lock to X (Exclusive). We have stumbled the same issue, thank you John for identifying the problem and sending us to the right direction.Īs John mentioned the issue is with the procedure. We have raised a call with ESRI support, but are looking for anyone else who may be having a similar problem, and better still, has a solution!. Putting these calls in half a dozen sql streams and running them all against each other (using a copy of live geodatabase with a "sde.SDE_state_locks�?� table populated with a few thousand dummy entries) I was able to reproduce the deadlock situation. The deadlock relates to objectname="sde.SDE_state_locks�?� table and is being called by sde.SDE_state_check_lock_conflicts and sde.SDE_state_lock_def_insert stored proceduresīy using SQL trace I was able to extract out lots of calls to these stored procedures. The error message from ArcObjects is: Īt the same time our SQL 2008R2 deadlock monitor reports a deadlock (and the victim is the one that gets the above error message) The error number from ArcObjects is: '-2147216072'. Please check that the connection parameters specified are correct. We also see the following in some of the FME jobs running at the same timeĬould not open the Enterprise Geodatabase. Ĭontainer process xxx has crashed on machine xxxx The base table definition string 'zzzzzz' is invalid. Under very heavy load (we were refreshing lots of cached area all at the same time) we get the following warning and error in ArcGIS log
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