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Re: 20020906 UCLA latencies

HI James,

I see we have tried the IP spoof to split the feeds, now we go one step
further.

Go into etc/hosts and create aliases for aeolus.ucsd.edu to 

aeolus1.ucsd.edu

aeolus2.ucsd.edu

aeolus3.ucsd.edu

Then, try splitting your DDPLUS|IDS feed (which is really one feedtype)
into:

request DDPLUS|IDS      "^[^S]" aeolus.ucsd.edu
request DDPLUS|IDS      "^S[AR]" aeolus1.ucsd.edu
request DDPLUS|IDS      "^S[^AR]" aeolus2.ucsd.edu

or 1,2,3 and use aeolus.ucsd.edu for another feed. We have found this to
be successful. 

Also, are you not requesting any NNEXRAD prods?
Do you want them?


I hope this works, let me know what you find out, and we will be watching
the stats!

Cheers,

-Jeff
____________________________                  _____________________
Jeff Weber                                    address@hidden
Unidata Support                               PH:303-497-8676 
COMET Case Study Library                      FX:303-497-8690
University Corp for Atmospheric Research      3300 Mitchell Ln
http://www.unidata.ucar.edu/staff/jweber      Boulder,Co 80307-3000
________________________________________      ______________________

On Mon, 9 Sep 2002, James Murakami wrote:

> Hi Jeff.
> 
> Yes, we've been suffering from high latencies much of the summer. For a while 
> I 
> thought it was TYPHOON's aging disks. So, I started up ldm on a separate, 
> newer 
> workstation (PERIDOT). Things worked fine on it though I never could get the 
> logs to be posted. Sometime in August, things returned to "normal" on 
> TYPHOON. 
> However, a few days before Labor Day, latency problems returned (plagued 
> PERIDOT 
> as well).
> 
> I tried all sorts of combinations, even to the point of ingesting only MCIDAS 
> data. Strangely, latencies last week were still horrible with that little 
> data 
> transmission. Shortly before you emailed me, transmissions seemed faster on 
> both 
> workstations. I increased the data load on both (MCIDAS/DDPLUS/FSL on TYPHOON 
> and UNIDATA/FSL on PERIDOT). It was less than hour latencies on TYPHOON but 
> sometimes over an hour on PERIDOT. Latencies were worse during the day than 
> at 
> night (about 7:30- 8AM, local time, onward into early evening). This has been 
> the case each day that I've monitored the activty (using ldmadmin watch).
> 
> I heard from my systems admin that UCLA is using packetshaper but only to 
> monitor the Internet flow into campus (not restricting data flow). Whenever I 
> do 
> traceroute, there seems to be nothing greatly slow. This is what I got this 
> morning (other days have been better even when latencies exceeded an hour):
> 
> 1528Z 9 Sep 2002
> 
> traceroute to aeolus.ucsd.edu (132.239.114.58), 30 hops max, 40 byte packets
>  1  psnet-ms77.atmos.ucla.edu (128.97.77.231)  1 ms  1 ms  1 ms
>  2  164.67.160.1 (164.67.160.1)  2 ms  2 ms  6 ms
>  3  mathsci--mathsci.backbone.ucla.net (169.232.9.1)  2 ms  2 ms  1 ms
>  4  mathsci--core.backbone.ucla.net (169.232.6.61)  2 ms  1 ms  1 ms
>  5  core--border.backbone.ucla.net (169.232.6.11)  2 ms  2 ms  1 ms
>  6  border--calren.backbone.ucla.net (169.232.35.11)  1 ms  2 ms  2 ms
>  7  ISI--UCLA.POS.calren2.net (198.32.248.29)  3 ms  2 ms  2 ms
>  8  USC--ISI.POS.calren2.net (198.32.248.25)  3 ms  3 ms  3 ms
>  9  UCSD--USC.POS.calren2.net (198.32.248.34)  6 ms  6 ms  6 ms
> 10  198.32.248.186 (198.32.248.186)  7 ms  7 ms  6 ms
> 11  sio-rsm--ucsd-gw.ucsd.edu (132.239.255.145)  9 ms  7 ms  7 ms
> 12  aeolus.ucsd.edu (132.239.114.58)  65 ms  57 ms  86 ms
> 
> traceroute to sunny89.atmos.washington.edu (128.95.89.38), 30 hops max, 40 
> byte
> packets
>  1  psnet-ms77.atmos.ucla.edu (128.97.77.231)  1 ms  1 ms  1 ms
>  2  164.67.160.1 (164.67.160.1)  2 ms  2 ms  1 ms
>  3  mathsci--mathsci.backbone.ucla.net (169.232.9.1)  2 ms  1 ms  2 ms
>  4  mathsci--core.backbone.ucla.net (169.232.6.61)  1 ms  1 ms  1 ms
>  5  core--border.backbone.ucla.net (169.232.6.11)  2 ms  2 ms  1 ms
>  6  border--calren.backbone.ucla.net (169.232.35.11)  2 ms  2 ms  1 ms
>  7  ISI--UCLA.POS.calren2.net (198.32.248.29)  2 ms  2 ms  2 ms
>  8  USC--ISI.POS.calren2.net (198.32.248.25)  3 ms  3 ms  3 ms
>  9  Abilene--USC.ATM.calren2.net (198.32.248.86)  3 ms  3 ms  3 ms
> 10  scrm-losa.abilene.ucaid.edu (198.32.8.17)  14 ms  10 ms  10 ms
> 11  sttl-snva.abilene.ucaid.edu (198.32.8.9)  28 ms  28 ms  28 ms
> 12  hnsp1-wes-so-5-0-0-0.pnw-gigapop.net (198.48.91.77)  29 ms  28 ms  29 ms
> 13  uwbr1-GE3-0.cac.washington.edu (198.107.151.51)  28 ms  28 ms  28 ms
> 14  dustbuster-V23.cac.washington.edu (140.142.153.2)  29 ms  29 ms  29 ms
> 15  sunny.atmos.washington.edu (128.95.89.38)  29 ms  29 ms  29 ms
> 
> 
> Wouldn't the traceroute show significant slowing if packetshaper were 
> limiting 
> the rate of flow? I'm also wondering if the "logjam" is occurring somewhere 
> between the UCLA campus and San Diego (when we're on aeolus.ucsd.edu). It's 
> strange that the latency occurs routinely by mid-morning (local time) and 
> pretty 
> much ends in the dead of night.
> 
> Anyway, any suggestions are welcome. I've attached a copy of my ldmd.conf 
> file. 
> You'll see various commented out data type requests. That's my attempts at 
> getting data without huge latencies. Currently, I see latencies of about 
> 30-40 
> minutes on TYPHOON and PERIDOT.
> 
> James 
> 
>  
> > 
> > Hello James, 
> > 
> > We are using some new diagnostics for network and LDM/IDD performance, and
> > we noticed you are still experiencing some large latencies.
> > 
> > We have come up with some ideas that may decrease latencies and improve
> > performance.
> > 
> > Could you please send me your ldmd.conf file so we can take a look at your
> > requests. Your network connectivity seems to be great, so there is no
> > reason to be experiencing these latencies. We have found some alternative
> > methods for requesting data (using aliases in etc/hosts) that has shown to
> > improve performance. I look forward to working on this with you.
> > 
> > Thank you, 
> > 
> > -Jeff
> > ____________________________                  _____________________
> > Jeff Weber                                    address@hidden
> > Unidata Support                               PH:303-497-8676 
> > COMET Case Study Library                      FX:303-497-8690
> > University Corp for Atmospheric Research      3300 Mitchell Ln
> > http://www.unidata.ucar.edu/staff/jweber      Boulder,Co 80307-3000
> > ________________________________________      ______________________
> > 
> 
> --------------------------------------
> James Murakami
> Staff Meteorologist/Student Affairs
> Department of Atmospheric Sciences
> University of California, Los Angeles
> 405 Hilgard Ave.
> Los Angeles, CA  90095-1565
> 
> 
>    e-mail:  address@hidden
> telephone:  310-825-2418
>       Fax:  310-206-5219
> ---------------------------------------
>