"Nsock performance drops under heavy load – any optimization tips?"
Hey folks,
Been using nsock for a while now, and it's mostly solid... but man, when the load spikes, things get *choppy*. Timeouts, delays, you name it.
Anyone else run into this? Maybe tweaked some settings that helped?
I’ve played with `--max-parallelism` and buffer sizes, but still seeing hiccups. Wondering if it’s just me or if others have hacks to share.
Also, does nsock handle IPv6 as smoothly as IPv4? Noticed some weirdness there too.
Thanks in advance!
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Yeah, nsock can be a pain under heavy load. One thing that helped me was tweaking the `--max-retries` setting—lowering it reduced some of the timeout chaos.
Also, check your system’s ulimit for open files. If nsock hits that cap, it’ll choke.
IPv6? Eh, it’s hit or miss. Sometimes it’s fine, other times it’s like nsock forgets how to IPv6 entirely.
I feel you on the IPv6 weirdness. nsock’s IPv6 support feels like an afterthought.
For heavy load, try splitting your workload into smaller batches. Less parallelism sometimes = more stability. Weird, but it worked for me.
Also, maybe give `libevent` a shot if nsock keeps acting up. It’s not a drop-in replacement, but it’s way more consistent under pressure.
nsock’s performance drops are usually a sysctl thing. Tune your TCP stack—increase `net.core.somaxconn` and `net.ipv4.tcp_max_syn_backlog`.
IPv6? Yeah, it’s janky. Stick to IPv4 unless you *need* v6.
Pro tip: Monitor with `iftop` or `nload` to see if it’s nsock or your network crapping out.
Had the same issue! Switched to `--send-retries 2` and bumped up the socket buffer sizes. Not perfect, but way fewer timeouts.
For IPv6, nsock *can* work, but you gotta babysit it. Check your kernel logs for weirdness.
Also, `strace` is your friend—see where nsock is spending all its time.
nsock + heavy load = pain. Try reducing `--max-hostgroup` if you’re scanning or whatever. Smaller chunks = less rage.
IPv6? Lol. Good luck. It’s *technically* supported, but I’ve seen it flake out for no reason.
If you’re desperate, maybe try `asyncns`? Not the same, but it’s less temperamental.
Yo, nsock under load is like a drunk driver—unpredictable.
Two things:
1. Set `--min-parallelism` higher than default. Sounds backwards, but it helps.
2. Disable IPv6 unless you *need* it. nsock’s v6 stack is... questionable.
Tool rec: `perf top` to spot bottlenecks.
Thanks for all the tips, folks!
Tried tweaking `--max-parallelism` and `--send-retries` like some of you suggested, and it’s *better*... but still not perfect.
Gonna dig into `sysctl` settings next. IPv6 is a lost cause, huh? Bummer.
Anyone tried nsock with kernel bypass stuff like DPDK? Or is that overkill?
(Also, `strace` was eye-opening—thanks for that!)
nsock’s perf drops are usually a kernel or NIC issue. Check for packet drops with `ethtool -S`.
IPv6? Yeah, it’s flaky. Try forcing nsock to v4-only with `--disable-ipv6` if you can.
Also, `sysdig` is gold for tracing nsock’s syscalls. Might reveal the culprit.
