I set the SHM size to 48G on my witness server (with 50GB RAM) and the server stopped to produce blocks with the following message:

2736622ms th_a database.cpp:2596 show_free_memory ] Free memory is now 50M. Increase shared file size immediately

I had to stop the node, increase the shared file size, mounted more spaced to /dev/shm. Meanwhile, I thought it would be a good idea to upgrade node from 0.19.5 to 0.19.6 using command ./run.sh install.

Also, I enabled zram which is to compress the RAM using LZO compression algorithm.

du -h /dev/shm/shared_memory.bin
49G     /dev/shm/shared_memory.bin

and the uncompressed size - which is the SHM size is set to 96GB - usually this number is suggested by the following:

SIZE = 2 * RAM - SWAP

The ZRAM let your node last a bit longer with the limited RAM size - however at the cost of speed because it takes efforts for processors to zip and unzip the RAM on the fly i.e. it takes a bit longer this time (around 40 hours reindexing time).

For steem re-indexing, the time required can be shortened if the CPU frequency is higher. Anyway, the node has produced two blocks since last re-enabled - everything seems good so far!

Being a steem witness is not easy, it takes efforts to maintain your server regularly e.g. applying updates/hardforks - this requires that you monitor (that is your duty) the healthy of your witness node from time to time (I check that every day - every few hours when I am awake - on my phone)

The latency is good and the witness is running smoothly

// Reposted to: https://helloacm.com/steem-witness-updated-to-0-19-6-and-server-using-zram/

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