Description of problem:
While add RHV provider using UI, cause the MTV UI to be stuck with error

"Danger alert:Error loading providers from inventory API
500: Internal Server Error"

While try to use 'Migration plan' get error
"Error loading providers
500: Internal Server Error"

While try to use 'Mappings' get error
"Error loading provider inventory data
500: Internal Server Error"


RHV info (scale env): ~4700VMs, 265 Hosts

Version-Release number of selected component (if applicable):

MTV_2.1.0-27
How reproducible:


Steps to Reproduce:
1. Adding RHV provider
2. After ~10-15seconds can't use MTV UI
3.

Actual results:

Can use MTV UI for ~10 minutes

Expected results:

MTV UI should be available for use

Additional info:

inventory log:

{"level":"info","ts":1626087031.6307125,"logger":"web|provider","msg":"","sql":"\nSELECT\nCOUNT(*)\nFROM DataCenter\n;\n","params":null,"url":"/providers?detail=1","error":"database is locked","stacktrace":"\ngithub.com/konveyor/controller/pkg/inventory/model.Table.Count()\n\t/remote-source/deps/gomod/pkg/mod/github.com/konveyor/controller.6/pkg/inventory/model/table.go:605\ngithub.com/konveyor/controller/pkg/inventory/model.(*Client).Count()\n\t/remote-source/deps/gomod/pkg/mod/github.com/konveyor/controller.6/pkg/inventory/model/client.go:197\ngithub.com/konveyor/forklift-controller/pkg/controller/provider/web/ovirt.ProviderHandler.AddDerived()\n\t/remote-source/app/pkg/controller/provider/web/ovirt/provider.go:139\ngithub.com/konveyor/forklift-controller/pkg/controller/provider/web/ovirt.(*ProviderHandler).ListContent()\n\t/remote-source/app/pkg/controller/provider/web/ovirt/provider.go:115\ngithub.com/konveyor/forklift-controller/pkg/controller/provider/web.ProviderHandler.List()\n\t/remote-source/app/pkg/controller/provider/web/provider.go:97\ngithub.com/gin-gonic/gin.(*Context).Next()\n\t/remote-source/deps/gomod/pkg/mod/github.com/gin-gonic/gin.3/context.go:161\ngithub.com/gin-gonic/gin.RecoveryWithWriter.func1()\n\t/remote-source/deps/gomod/pkg/mod/github.com/gin-gonic/gin.3/recovery.go:83\ngithub.com/gin-gonic/gin.(*Context).Next()\n\t/remote-source/deps/gomod/pkg/mod/github.com/gin-gonic/gin.3/context.go:161\ngithub.com/gin-gonic/gin.LoggerWithConfig.func1()\n\t/remote-source/deps/gomod/pkg/mod/github.com/gin-gonic/gin.3/logger.go:241\ngithub.com/gin-gonic/gin.(*Context).Next()\n\t/remote-source/deps/gomod/pkg/mod/github.com/gin-gonic/gin.3/context.go:161\ngithub.com/gin-gonic/gin.(*Engine).handleHTTPRequest()\n\t/remote-source/deps/gomod/pkg/mod/github.com/gin-gonic/gin.3/gin.go:409\ngithub.com/gin-gonic/gin.(*Engine).ServeHTTP()\n\t/remote-source/deps/gomod/pkg/mod/github.com/gin-gonic/gin.3/gin.go:367\nnet/http.serverHandler.ServeHTTP()\n\t/usr/lib/golang/src/net/http/server.go:2855\nnet/http.(*conn).serve()\n\t/usr/lib/golang/src/net/http/server.go:1937\nruntime.goexit()\n\t/usr/lib/golang/src/runtime/asm_amd64.s:1374"}
[GIN] 2021/07/12 - 10:50:31 | 500 |  5.010971351s |   192.168.208.1 | GET      "/providers?detail=1"
[GIN] 2021/07/12 - 10:50:39 | 500 |  5.011393588s |   192.168.208.1 | GET      "/providers?detail=1"