aere-network/aere-node
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

RUN-A-NODE: the measured RAM figure for a from-genesis import. The requirement grows with the height: the same import that ran comfortably at 3 M blocks was, at 12.2 M, using 5.96 GB resident with a 3.4 GB heap, old generation 99.8 percent full, four full GCs every five seconds, and no room left to raise the heap. 8 GB is the floor at which a full import stops being practical, not a comfortable size

Browse Source
This commit is contained in:
Aere Network 2026-09-06 20:14:52 +03:00
parent 84a6093517
commit b46c815398
1 changed files with 9 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
RUN-A-NODE.md
View File

@ -179,6 +179,15 @@ and the node dies of `OutOfMemoryError`. But a heap that is too small is just as
direction: past block 9,189,161, where the post-quantum precompiles go live, blocks get heavier, the old direction: past block 9,189,161, where the post-quantum precompiles go live, blocks get heavier, the old
generation fills, and the node spends its time in full GC instead of importing. generation fills, and the node spends its time in full GC instead of importing.
**How much RAM a from-genesis import needs, measured.** The requirement is not flat: it grows with the
height, because the storage engine's working set grows with the chain. On the machine above (8 GB for
the node), the same import that ran comfortably at three million blocks was, at 12.2 million, using
5.96 GB of resident memory with a 3.4 GB heap, with the old generation 99.8% full and four full GCs
every five seconds - and there was no room left to raise the heap without hitting `OutOfMemoryError`
instead. Treat 8 GB as the floor at which a full from-genesis import stops being practical, not as a
comfortable size; 16 GB gives the database the room this measurement shows it wants. Following the
live tip, once synced, needs far less: the network's own reading nodes do it inside their normal
footprint.
So do not pick a fraction of RAM and hope. Watch it: `jstat -gcutil <pid> 5000 3` prints one line every So do not pick a fraction of RAM and hope. Watch it: `jstat -gcutil <pid> 5000 3` prints one line every
five seconds. If `FGC` climbs while the height barely moves, the heap is too SMALL - raise it. If you see five seconds. If `FGC` climbs while the height barely moves, the heap is too SMALL - raise it. If you see
`OutOfMemoryError` in the log, it is too LARGE for what the database also needs - lower it. On 8 GB, the `OutOfMemoryError` in the log, it is too LARGE for what the database also needs - lower it. On 8 GB, the