Re: [Devel-spam] FuzzyOcr 3.5.1 released
Heute (12.01.2007/11:51 Uhr) schrieb A Mennucc, > hi > netpbm in Debian is 10.1 ; so it is too old > I asked for a newer one in > http://bugs.debian.org/159847 > Jim Knuth ha scritto: >> >> I`ve forgotten: libnetpbm10-dev (Debian Etch) >> >> > what do you mean by this ? I mean: This is also installed. ;) > a. -- Viele Gruesse, Kind regards, Jim Knuth [EMAIL PROTECTED] ICQ #277289867 -- Zufalls-Zitat -- Freiheit bedeutet Verantwortlichkeit; das ist der Grund, warum sich die meisten Menschen vor ihr fürchten. (George Bernard Shaw, ir. Dramatiker, 1856-1950) -- Der Text hat nichts mit dem Empfaenger der Mail zu tun -- Virus free. Checked by NOD32 Version 1973 Build 8755 12.01.2007
Re: [Devel-spam] FuzzyOcr 3.5.1 released
hi netpbm in Debian is 10.1 ; so it is too old I asked for a newer one in http://bugs.debian.org/159847 Jim Knuth ha scritto: > > I`ve forgotten: libnetpbm10-dev (Debian Etch) > > what do you mean by this ? a. signature.asc Description: OpenPGP digital signature
Re: [Devel-spam] FuzzyOcr 3.5.1 released
Yup - if you are looking for "within 10 miles" you can perform a raw
comparison by looking at the lat-lon degrees number to remove anything
more than two degrees apart. That knocks down your search by 180 time
in each direction, over 3:1 savings right there. If you store all
the data as degree and fractional degree you can remove everything more
than a small fraction of a degree apart.
But for the first cut storing everything in the grid square 117 to 118
longitude and 34 to 35 longitude in its own part of the tree structure
allows almost instant selection of "likely" candidates. You could also
use links to store 117 to 118, 34-35 in one box, 117.5-118.5, 34-35 in
another box - noting the overlap in the concept. That means a site right
on a corner or edge of a criterion marker isn't lost. Anything like that
which can be used to reduce the amount of data that needs to be tested
even at the expence of cross-linked trees is a huge savings. You enter
an item into the database once, that performs the searches for the crude
region linkages. Then the searches, the "many" operation, can proceed
quicker due to filtering out excess searches.
{^_^}
- Original Message -
From: "Dan Barker" <[EMAIL PROTECTED]>
Giampaolo: I hope you succeed.
I've given up hope on convincing folks (Mapquest in particular) that
radius
searches can be indexed. You needn't pull the lat/long of every single
entry
to run the distance function, and then discard the ones too far away. You
can index on LAT and LONG and structure the query such that only the
"possible" lat/long values need the distance function (and the rest of the
record fetched) evaluated.
Just because it's two orders of magnitude more efficient doesn't make
anybody listen.
Same conversation, different universe!
Dan
-Original Message-
From: Giampaolo Tomassoni [mailto:[EMAIL PROTECTED]
From: Andy Dills [mailto:[EMAIL PROTECTED]
...omissis...
> I understand that the "order" keyword in select is potentially
expensive, but
> necessary because matches occur generally towards the most
recent entries,
> thus increasing the possibility of a match earlier on. When
your hash count
> is in the thousands, earlier matches mean less queries to the
database, and
> potentially faster results.
It's not just the order directive, it's the iteration throughout the
entire database.
Consider when the database grows to >50k records. For a new image that
doesn't have a hash, that's 50k records that must be sorted then
sent from
the DB server to the mail server, then all 50k records must be checked
against the hash before we decide that we haven't seen this image before.
That just isn't a workable algorithm. If iteration throughout the entire
database is a requirement, hashing is a performance hit rather than a
performance gain.
A better solution might be a seperate daemon that holds the hashes in
memory, to which you submit the hash being considered.
Other ways could be the ones depicted in my recent post (Message-ID:
<[EMAIL PROTECTED]>), in which close
images
are basicly clustered together thanks to a surrogate index.
giampaolo
Honestly, I have been extremely impressed with having hashing turned
completely off.
Andy
---
Andy Dills
Xecunet, Inc.
www.xecu.net
301-682-9972
---
Re: [Devel-spam] FuzzyOcr 3.5.1 released
Andy Dills wrote: On Mon, 8 Jan 2007, Jorge Valdes wrote: I do understand that in large environments, optimizations have to be made in order not to kill server performance, and expiration is probably something that could be done at "more convenient times". I will commit a script that can safely be run as a cronjob soon. Excellent. I understand that the "order" keyword in select is potentially expensive, but necessary because matches occur generally towards the most recent entries, thus increasing the possibility of a match earlier on. When your hash count is in the thousands, earlier matches mean less queries to the database, and potentially faster results. It's not just the order directive, it's the iteration throughout the entire database. Consider when the database grows to >50k records. For a new image that doesn't have a hash, that's 50k records that must be sorted then sent from the DB server to the mail server, then all 50k records must be checked against the hash before we decide that we haven't seen this image before. That just isn't a workable algorithm. If iteration throughout the entire database is a requirement, hashing is a performance hit rather than a performance gain. A better solution might be a seperate daemon that holds the hashes in memory, to which you submit the hash being considered. Honestly, I have been extremely impressed with having hashing turned completely off. Andy --- Andy Dills Xecunet, Inc. www.xecu.net 301-682-9972 --- Right now my DB is ~21K records, and I expire after 21 days... I could always reduce the size of the DB by expiring sooner. The default value is set for 35 days, a little over one month (5 full weeks), so tunning this value could help you out. After looking at my logs, ~2/3 of the matches happen within 24hrs, so just keeping matches for 24 hours will get me 2/3 of the way, as you can always rescan the images from the other 1/3 of the messages and will probably be faster than looking for the database match in your case. Remember, when working in large environments, optimization of resources is key, so here are a few suggestions: + expiring the DB after only 1-3 days may be the optimal setting for you, since this will reduce the number of records in the DB and still reap the benefits of saving the hashes. Check your logs... + use BerkeleyDB on a Ramdisk will certainly be faster, just make sure that the Ramdisk will not run out of free space (not generally a problem). Also, remember to save a copy from Ramdisk to Harddisk periodically in order to keep backups in case of a system restart, or you will loose the DB. + tune your MySQL setup, including but not limited to adding another index: 'Hash.check' in order to reduce the sorting times, allocation more RAM for sorting, etc. + use a dedicated MySQL server if you use the MySQL solution to share the database among several SMTP servers, possibly using this server for other common tasks as well. Remember, that the solution you may implement depends largely on the resources you have available. There are other solutions that can help you reduce the amount of work sent to the plugin, the Botnet plugin helps a lot, and setting *focr_autodisable_score* to a value more suited to your situation (default: 10), since most people set it to a higher value in order to test the plugin and never reset this value. Jorge.
RE: [Devel-spam] FuzzyOcr 3.5.1 released
From: Dan Barker [mailto:[EMAIL PROTECTED] > > Giampaolo: I hope you succeed. > > I've given up hope on convincing folks (Mapquest in particular) > that radius > searches can be indexed. You needn't pull the lat/long of every > single entry > to run the distance function, and then discard the ones too far away. You > can index on LAT and LONG and structure the query such that only the > "possible" lat/long values need the distance function (and the rest of the > record fetched) evaluated. Right. > Just because it's two orders of magnitude more efficient doesn't make > anybody listen. > > Same conversation, different universe! You mean that it is probably a concept to far away from the origin of someone's comprehensibility space? :) giampaolo > Dan > > -Original Message- > From: Giampaolo Tomassoni [mailto:[EMAIL PROTECTED] > Sent: Monday, January 08, 2007 2:00 PM > To: [EMAIL PROTECTED]; users@spamassassin.apache.org > Subject: RE: [Devel-spam] FuzzyOcr 3.5.1 released > > > From: Andy Dills [mailto:[EMAIL PROTECTED] > > > > ...omissis... > > > > > I understand that the "order" keyword in select is potentially > > expensive, but > > > necessary because matches occur generally towards the most > > recent entries, > > > thus increasing the possibility of a match earlier on. When > > your hash count > > > is in the thousands, earlier matches mean less queries to the > > database, and > > > potentially faster results. > > > > It's not just the order directive, it's the iteration throughout the > > entire database. > > > > Consider when the database grows to >50k records. For a new image that > > doesn't have a hash, that's 50k records that must be sorted then > > sent from > > the DB server to the mail server, then all 50k records must be checked > > against the hash before we decide that we haven't seen this > image before. > > That just isn't a workable algorithm. If iteration throughout the entire > > database is a requirement, hashing is a performance hit rather than a > > performance gain. > > > > A better solution might be a seperate daemon that holds the hashes in > > memory, to which you submit the hash being considered. > > Other ways could be the ones depicted in my recent post (Message-ID: > <[EMAIL PROTECTED]>), in which > close images > are basicly clustered together thanks to a surrogate index. > > giampaolo > > > > > Honestly, I have been extremely impressed with having hashing turned > > completely off. > > > > Andy > > > > --- > > Andy Dills > > Xecunet, Inc. > > www.xecu.net > > 301-682-9972 > > --- > >
RE: [Devel-spam] FuzzyOcr 3.5.1 released
Giampaolo: I hope you succeed. I've given up hope on convincing folks (Mapquest in particular) that radius searches can be indexed. You needn't pull the lat/long of every single entry to run the distance function, and then discard the ones too far away. You can index on LAT and LONG and structure the query such that only the "possible" lat/long values need the distance function (and the rest of the record fetched) evaluated. Just because it's two orders of magnitude more efficient doesn't make anybody listen. Same conversation, different universe! Dan -Original Message- From: Giampaolo Tomassoni [mailto:[EMAIL PROTECTED] Sent: Monday, January 08, 2007 2:00 PM To: [EMAIL PROTECTED]; users@spamassassin.apache.org Subject: RE: [Devel-spam] FuzzyOcr 3.5.1 released From: Andy Dills [mailto:[EMAIL PROTECTED] > > ...omissis... > > > I understand that the "order" keyword in select is potentially > expensive, but > > necessary because matches occur generally towards the most > recent entries, > > thus increasing the possibility of a match earlier on. When > your hash count > > is in the thousands, earlier matches mean less queries to the > database, and > > potentially faster results. > > It's not just the order directive, it's the iteration throughout the > entire database. > > Consider when the database grows to >50k records. For a new image that > doesn't have a hash, that's 50k records that must be sorted then > sent from > the DB server to the mail server, then all 50k records must be checked > against the hash before we decide that we haven't seen this image before. > That just isn't a workable algorithm. If iteration throughout the entire > database is a requirement, hashing is a performance hit rather than a > performance gain. > > A better solution might be a seperate daemon that holds the hashes in > memory, to which you submit the hash being considered. Other ways could be the ones depicted in my recent post (Message-ID: <[EMAIL PROTECTED]>), in which close images are basicly clustered together thanks to a surrogate index. giampaolo > > Honestly, I have been extremely impressed with having hashing turned > completely off. > > Andy > > --- > Andy Dills > Xecunet, Inc. > www.xecu.net > 301-682-9972 > ---
RE: [Devel-spam] FuzzyOcr 3.5.1 released
From: Andy Dills [mailto:[EMAIL PROTECTED] > > ...omissis... > > > I understand that the "order" keyword in select is potentially > expensive, but > > necessary because matches occur generally towards the most > recent entries, > > thus increasing the possibility of a match earlier on. When > your hash count > > is in the thousands, earlier matches mean less queries to the > database, and > > potentially faster results. > > It's not just the order directive, it's the iteration throughout the > entire database. > > Consider when the database grows to >50k records. For a new image that > doesn't have a hash, that's 50k records that must be sorted then > sent from > the DB server to the mail server, then all 50k records must be checked > against the hash before we decide that we haven't seen this image before. > That just isn't a workable algorithm. If iteration throughout the entire > database is a requirement, hashing is a performance hit rather than a > performance gain. > > A better solution might be a seperate daemon that holds the hashes in > memory, to which you submit the hash being considered. Other ways could be the ones depicted in my recent post (Message-ID: <[EMAIL PROTECTED]>), in which close images are basicly clustered together thanks to a surrogate index. giampaolo > > Honestly, I have been extremely impressed with having hashing turned > completely off. > > Andy > > --- > Andy Dills > Xecunet, Inc. > www.xecu.net > 301-682-9972 > ---
Re: [Devel-spam] FuzzyOcr 3.5.1 released
On Mon, 8 Jan 2007, Jorge Valdes wrote: > I do understand that in large environments, optimizations have to be made in > order not to kill server performance, and expiration is probably something > that could be done at "more convenient times". I will commit a script that > can safely be run as a cronjob soon. Excellent. > I understand that the "order" keyword in select is potentially expensive, but > necessary because matches occur generally towards the most recent entries, > thus increasing the possibility of a match earlier on. When your hash count > is in the thousands, earlier matches mean less queries to the database, and > potentially faster results. It's not just the order directive, it's the iteration throughout the entire database. Consider when the database grows to >50k records. For a new image that doesn't have a hash, that's 50k records that must be sorted then sent from the DB server to the mail server, then all 50k records must be checked against the hash before we decide that we haven't seen this image before. That just isn't a workable algorithm. If iteration throughout the entire database is a requirement, hashing is a performance hit rather than a performance gain. A better solution might be a seperate daemon that holds the hashes in memory, to which you submit the hash being considered. Honestly, I have been extremely impressed with having hashing turned completely off. Andy --- Andy Dills Xecunet, Inc. www.xecu.net 301-682-9972 ---
