System information

Geth version: geth version 1.5.9-stable, Go1.7.4
OS & Version: OSX 10.12.6 MacMini 4GB RAM (latest MacMini doesn't support field RAM upgrade anymore) VDSL connection with an average of 20-40Mbit throughput. Ethereum Wallet 0.9.0
Commit hash : (if develop)

Expected behaviour

fast sync to current latest block followed by auto disabling

Actual behaviour

stalling from a few thousand blocks up to a few hundred to current latest block. Tries to catch up to latest block, but number of new blocks is greater than the speed of adding fast blocks. Never auto disables fast sync mode.

Steps to reproduce the behaviour

Removedb and geth --fast --cache=1024. 5 times on that machine over the last weeks.

Fast sync is already my workaround, starting a fresh fast sync from scratch. Before I was unsuccessful on that machine trying to sync with existing blockchain data instead. This was also a lost race of catching up to the latest block on that machine. This workaround was good until now.

Today even the workaround in fast sync mode (cache -1024) will not completely load the blockchain anymore. It catches up some hundred blocks to the latest block and stalls for hours. By the time it catches up a few hundred blocks, the latest block moved ahead again. The closer geth is getting to import to the latest block (at time of writing 4173161), the slower it gets. It does not catch up anymore. Tried 5 times now over the last weeks and giving up at around 4-5 days each.

Does the machine not meet todays minimum hardware requirement anymore or is this a major bug?

Backtrace

latest block 13 hours ago (!)

I0818 00:15:26.444933 core/blockchain.go:805] imported 148 receipts in 2.775s. #4169952 [e3f556fc… / 36f4d3c9…]

...

latest header chain 50 minutes ago

I0818 12:47:45.107445 core/headerchain.go:342] imported 1 headers in 4.954ms. #4173009 [350d1426… / 350d1426…]

...

currently only importing nothing but state entries

I0818 13:36:41.103101 eth/downloader/downloader.go:966] imported 172 state entries in 10.009s: processed 10010213, pending at least 129361
I0818 13:36:41.103131 eth/downloader/downloader.go:966] imported 384 state entries in 783.519ms: processed 10010597, pending at least 129361
I0818 13:36:41.103154 eth/downloader/downloader.go:966] imported 381 state entries in 6.963s: processed 10010978, pending at least 129361
I0818 13:36:41.103167 eth/downloader/downloader.go:966] imported 25 state entries in 87.654ms: processed 10011003, pending at least 129360
I0818 13:36:46.014244 eth/downloader/downloader.go:966] imported 384 state entries in 2.482s: processed 10011387, pending at least 127584
I0818 13:36:49.074483 eth/downloader/downloader.go:966] imported 381 state entries in 7.082s: processed 10011768, pending at least 127105
I0818 13:36:49.074553 eth/downloader/downloader.go:966] imported 384 state entries in 7.971s: processed 10012152, pending at least 127105
I0818 13:36:49.074574 eth/downloader/downloader.go:966] imported 384 state entries in 3.772s: processed 10012536, pending at least 127105
I0818 13:36:49.074603 eth/downloader/downloader.go:966] imported 162 state entries in 5.822s: processed 10012698, pending at least 127105
I0818 13:36:49.074622 eth/downloader/downloader.go:966] imported 25 state entries in 4.050s: processed 10012723, pending at least 127105
I0818 13:36:49.074639 eth/downloader/downloader.go:966] imported 381 state entries in 3.060s: processed 10013104, pending at least 127105
I0818 13:36:49.074742 eth/downloader/downloader.go:966] imported 85 state entries in 7.117s: processed 10013189, pending at least 127105
I0818 13:36:49.074765 eth/downloader/downloader.go:966] imported 375 state entries in 2.219s: processed 10013564, pending at least 127105
I0818 13:36:49.074782 eth/downloader/downloader.go:966] imported 87 state entries in 3.915s: processed 10013651, pending at least 127105
I0818 13:36:49.074795 eth/downloader/downloader.go:966] imported 23 state entries in 271.734ms: processed 10013674, pending at least 127104