Light client hangs after some time of work

[pdgsmf79]

Operating System - Debian 9.5 Linux
Installation - Tried *.deb file from website and precompiled binary from github
Fully syncronized - yes
Network - ropsten and mainnet

Parity stops responding after running a while. Neither it updates blockchain, nor responds to RPC calls via HTTP or WS
Every time it hangs, i cannot stop it by CTRL+C combination and have to kill it.
It happens without any schedule. Can happen right after start and can happen after a day of running.
I have tried different versions, starting from 1.10 and all of them have the same issue.
Also tried on other machines under Ubuntu 18.04. All the same.
I start parity with the following command:

parity --chain=ropsten --light --jsonrpc-interface=all --jsonrpc-hosts=all

With such an issue I cannot rely on parity as a node software, since my project require high availability.

[Tbaut]

Can you please share the logs and trace with -l rpc for instance?
This might be related to other issues such as: #9551

Do you have the same problem on Kovan ? (Ropsten isnt't the best choice of testnet due to the lack of peers)

[Tbaut]

Closing as stale

[cryptoqube777]

Anyway light client hangs. No suspicious data in logs, everything just as usual
Tried on two different PCs, one under Debian 9 and another under Ubuntu 18.04
Tried different versions. Tried both Ropsten and Mainnet
I run parity with command:
parity --light -l sync=debug,rpc=trace

Still no ideas how to fix it?

[cryptoqube777]

Last lines of log:

2018-10-23 20:07:36  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:36  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:36  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:36  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:36  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:36  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:36  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:36  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:37  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:37  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:39  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:41  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:41  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:44  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:45  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:45  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:45  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:45  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:45  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:46  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:46  IO Worker #2 DEBUG sync  Found common ancestor with best chain
2018-10-23 20:07:46  IO Worker #2 DEBUG sync  Maintaining sync (AncestorSearch(FoundCommon(6569764, 0x686ed5ca946c3c20cf75db9376db164d16b70db7ca902cf8276e9a4f2bbae3ec)))
2018-10-23 20:07:46  IO Worker #1 DEBUG sync  Maintaining sync (Rounds(Aborted: TargetReached, 1 remain))
2018-10-23 20:07:46  IO Worker #1 DEBUG sync  Sync target reached. Going idle
2018-10-23 20:07:47  Verifier #0 INFO import  Imported #6569765 0xff64…e73a (7.98 Mgas)
2018-10-23 20:07:47  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:47  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:47  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:48  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:48  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:48  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:49  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:49  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:49  IO Worker #0 INFO import    25/50 peers   118 KiB cache 0 bytes queue  RPC:  0 conn,    0 req/s,   53 µs
2018-10-23 20:07:49  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:50  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:53  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:54  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:55  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:58  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:58  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:59  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:07:59  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:01  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:04  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:07  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:07  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:09  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:11  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:13  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:13  IO Worker #1 DEBUG sync  Maintaining sync (AncestorSearch(Awaiting(ReqId(262), 6569765, Complete { start: Number(6569765), skip: 0, max: 64, reverse: true })))
2018-10-23 20:08:13  IO Worker #3 DEBUG sync  Found common ancestor with best chain
2018-10-23 20:08:13  IO Worker #3 DEBUG sync  Maintaining sync (AncestorSearch(FoundCommon(6569764, 0x686ed5ca946c3c20cf75db9376db164d16b70db7ca902cf8276e9a4f2bbae3ec)))
2018-10-23 20:08:13  IO Worker #0 DEBUG sync  Maintaining sync (Rounds(Aborted: TargetReached, 2 remain))
2018-10-23 20:08:13  IO Worker #0 DEBUG sync  Sync target reached. Going idle
2018-10-23 20:08:13  Verifier #1 INFO import  Imported #6569765 0xbde0…40e4 (6.73 Mgas)
2018-10-23 20:08:13  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:14  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:14  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:14  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:14  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:14  IO Worker #3 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:14  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:15  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:15  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:15  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:16  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:17  IO Worker #0 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:18  IO Worker #2 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:19  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:19  IO Worker #3 INFO import    25/50 peers   119 KiB cache 0 bytes queue  RPC:  0 conn,    0 req/s,   53 µs
2018-10-23 20:08:20  IO Worker #1 DEBUG sync  Maintaining sync (Idle)
2018-10-23 20:08:20  IO Worker #1 DEBUG sync  Maintaining sync (AncestorSearch(Awaiting(ReqId(264), 6569766, Complete { start: Number(6569766), skip: 0, max: 64, reverse: true })))
2018-10-23 20:08:20  IO Worker #2 DEBUG sync  Found common ancestor with best chain
2018-10-23 20:08:20  IO Worker #2 DEBUG sync  Maintaining sync (AncestorSearch(FoundCommon(6569766, 0x3c97df5d0009b2bc1c21dbeab2d80f9f46f89f91ccb5119fdc51020ca4da5fbb)))
2018-10-23 20:08:20  IO Worker #0 DEBUG sync  Maintaining sync (Rounds(Scaffolding from (6569766, 0x3c97df5d0009b2bc1c21dbeab2d80f9f46f89f91ccb5119fdc51020ca4da5fbb)))
2018-10-23 20:08:20  IO Worker #3 DEBUG sync  Maintaining sync (Rounds(Scaffolding from (6569766, 0x3c97df5d0009b2bc1c21dbeab2d80f9f46f89f91ccb5119fdc51020ca4da5fbb)))
2018-10-23 20:08:20  IO Worker #1 DEBUG sync  Maintaining sync (Rounds(Aborted: NoResponses, 1 remain))
2018-10-23 20:08:20  IO Worker #1 DEBUG sync  Beginning search after aborted sync round

[cryptoqube777]

Parity version - 2.0.7

[cryptoqube777]

Also tried yesterday on another VPS, 16GB ram, 8 CPU, 250GB SSD
without --light key, just ./parity. It hung after 10 minutes of running.

[niklasad1]

@travelvee

Can you provide the following:

1. How many peers do you have? (Can be retrieved either from the net_peercount RPC or the import log)
2. Are you performing any RPC's via the JSON-RPC interface? (If you doing requests often the peers might disconnect you or you might run out of credits)

[cryptoqube777]

10 net peers.
Hangs with or without rpc requests - doesn't matter. Last one hung when I just started parity for the first time to download blockchain.

[cryptoqube777]

Well looks like this should be considered a feature of parity, rather than a bug. Unfortunately will have to move back to geth, which looks much more stable. Hope in newer versions this will be fixed.