"istioctl version" and envoy sidecar start is super slow (1.4.6)

“istioctl version” takes 1.30 minutes in one of a cluster, also the pods with istio sidecar takes ~5-7 minutes to start.

pods without istio sidecar start quickly on the same k8 cluster, so the slowness appears to be due to istio only

any pointers where can i look?

here is istio-proxy logs from one of a pod which took more time to start, timestamp in last 2 lines show the delay in minutes before envoy proxy is ready.

2020-05-18T03:25:41.742961Z	info	Epoch 0 starting
2020-05-18T03:25:41.746439Z	info	Envoy command: [-c /etc/istio/proxy/envoy-rev0.json --restart-epoch 0 --drain-time-s 45 --parent-shutdown-time-s 60 --service-cluster curl-pod.default --service-node sidecar~ --max-obj-name-len 189 --local-address-ip-version v4 --log-format [Envoy (Epoch 0)] [%Y-%m-%d %T.%e][%t][%l][%n] %v -l warning --component-log-level misc:error --concurrency 2]
[Envoy (Epoch 0)] [2020-05-18 03:25:41.780][20][warning][config] [bazel-out/k8-opt/bin/external/envoy/source/common/config/_virtual_includes/grpc_stream_lib/common/config/grpc_stream.h:91] gRPC config stream closed: 14, no healthy upstream
[Envoy (Epoch 0)] [2020-05-18 03:25:41.780][20][warning][config] [bazel-out/k8-opt/bin/external/envoy/source/common/config/_virtual_includes/grpc_stream_lib/common/config/grpc_stream.h:54] Unable to establish new stream

[Envoy (Epoch 0)] [2020-05-18 03:31:06.079][20][warning][config] [bazel-out/k8-opt/bin/external/envoy/source/common/config/_virtual_includes/grpc_stream_lib/common/config/grpc_stream.h:91] gRPC config stream closed: 13, 

2020-05-18T03:31:43.495382Z	info	Envoy proxy is ready

in case anyone comes here:

one of a worker node was bad, 90% pods running on that worker node were not in Running state, so there was a slowness in starting envoy, removing that node fixed the issue of envoy taking time to start.

istioctl version command slowness is still there, it takes a minute and half to return the version that i will deal later