| Quote from: 11110_110 |
Using DNSBench tends to flood my Router if I try to test too many servers at once.
|
Possibly exhausts the session table?
According to DNS Benchmark, on this low latency link, the RPi is only a couple of ms behind PlusNet's servers when it comes to doing its own
recursion, which is impressive.
In real world use, the few ms gained from the cache and the consistency of the performance more than make up for that (plus there's an additional perceived speed gain from ad filtering if implemented).
Obviously, on a higher latency link the gain from the cache is even greater, and it makes sense to use other servers with large caches as upstream resolvers.
I found things were slower when I forwarded queries upstream to PlusNet's servers (probably because of patchy slow responses or time-outs,) so I figured better to do it ourselves.
[tt]
212.159. 6. 9 | Min | Avg | Max |Std.Dev|Reliab%|
----------------+-------+-------+-------+-------+-------+
- Cached Name | 0.003 | 0.004 | 0.005 | 0.000 | 100.0 |
- Uncached Name | 0.004 | 0.068 | 0.311 | 0.090 | 100.0 |
- DotCom Lookup | 0.004 | 0.059 | 0.113 | 0.042 | 100.0 |
---<O-OO---->---+-------+-------+-------+-------+-------+
cdns01.plus.net
Rpi Unbound | Min | Avg | Max |Std.Dev|Reliab%|
----------------+-------+-------+-------+-------+-------+
+ Cached Name | 0.001 | 0.001 | 0.001 | 0.000 | 100.0 |
+ Uncached Name | 0.006 | 0.080 | 0.360 | 0.095 | 100.0 |
+ DotCom Lookup | 0.007 | 0.056 | 0.118 | 0.039 | 100.0 |
---<OOOO---->---+-------+-------+-------+-------+-------+
Local Network Nameserver
[/tt]
The figures I'm getting seem very consistent with 11110_110's using OpenDNS for recursion, in fact -- the difference being in the lower latency of our line.
The RPi processor load goes up to
6.3% for the Unbound process during the benchmarking. Definitely not stressing the Pi!
This is what I get as a benchmark for OpenDNS directly, for comparison:
[tt]
208. 67.222.222 | Min | Avg | Max |Std.Dev|Reliab%|
----------------+-------+-------+-------+-------+-------+
- Cached Name | 0.004 | 0.004 | 0.004 | 0.000 | 100.0 |
- Uncached Name | 0.004 | 0.076 | 0.275 | 0.087 | 100.0 |
- DotCom Lookup | 0.041 | 0.042 | 0.044 | 0.001 | 100.0 |
---<-------->---+-------+-------+-------+-------+-------+
resolver1.opendns.com
[/tt]
