Compression Filter
I'm trying to implement a compression filter on the HTTP response similar to that discussed in http://www.onjava.com/pub/a/onjava/2003/11/19/filters.html?page=1. When requesting straight JSP's, it works fine, but any Struts .dos do not work. Specifically, it appears the compression filter itself functions normally, but the browser responds with an empty page. (The source code, cryptically enough, does include htmlbody/body/html, but I suspect that's being defaulted somewhere.) I've tried: - Configuring the filter to handle *.do as a url-pattern, instead of the servlet-name action. - Commenting out the compression code entirely, leaving only GZIPResponseWrapper wrappedResponse = new GZIPResponseWrapper(res); chain.doFilter(req, wrappedResponse); - Executing the compression on a subclass of ActionServlet (after the super's doGet/doPost are called). ...but still the same results. We are running Struts on Sybase EAServer 4.2, by the way. Thanks in advance, Shahak Nagiel Software Engineer Northrop Grumman Mission Systems - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Compression Filter
Check your server logs for exceptions that say the response has already been committed. We had a programmer try to create a compression filter based on the source from one of those articles and it did not work on our production servers. Worth a look... -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Tuesday, March 09, 2004 2:56 PM To: [EMAIL PROTECTED] Subject: Compression Filter I'm trying to implement a compression filter on the HTTP response similar to that discussed in http://www.onjava.com/pub/a/onjava/2003/11/19/filters.html?page=1. When requesting straight JSP's, it works fine, but any Struts .dos do not work. Specifically, it appears the compression filter itself functions normally, but the browser responds with an empty page. (The source code, cryptically enough, does include htmlbody/body/html, but I suspect that's being defaulted somewhere.) I've tried: - Configuring the filter to handle *.do as a url-pattern, instead of the servlet-name action. - Commenting out the compression code entirely, leaving only GZIPResponseWrapper wrappedResponse = new GZIPResponseWrapper(res); chain.doFilter(req, wrappedResponse); - Executing the compression on a subclass of ActionServlet (after the super's doGet/doPost are called). ...but still the same results. We are running Struts on Sybase EAServer 4.2, by the way. Thanks in advance, Shahak Nagiel Software Engineer Northrop Grumman Mission Systems - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Compression Filter
Indeed, I got the exceptions you mentioned. Presumably, this is because requests for .dos ultimately either forward or redirect to JSP's, and, I believe, either one will flush the response buffer and hence commit the response. So, does this mean there's no way to enable a filter-based compression with Struts? -Original Message- From: Hookom, Jacob [mailto:[EMAIL PROTECTED] Sent: Tuesday, March 09, 2004 4:04 PM To: Struts Users Mailing List Subject: RE: Compression Filter Check your server logs for exceptions that say the response has already been committed. We had a programmer try to create a compression filter based on the source from one of those articles and it did not work on our production servers. Worth a look... -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Tuesday, March 09, 2004 2:56 PM To: [EMAIL PROTECTED] Subject: Compression Filter I'm trying to implement a compression filter on the HTTP response similar to that discussed in http://www.onjava.com/pub/a/onjava/2003/11/19/filters.html?page=1. When requesting straight JSP's, it works fine, but any Struts .dos do not work. Specifically, it appears the compression filter itself functions normally, but the browser responds with an empty page. (The source code, cryptically enough, does include htmlbody/body/html, but I suspect that's being defaulted somewhere.) I've tried: - Configuring the filter to handle *.do as a url-pattern, instead of the servlet-name action. - Commenting out the compression code entirely, leaving only GZIPResponseWrapper wrappedResponse = new GZIPResponseWrapper(res); chain.doFilter(req, wrappedResponse); - Executing the compression on a subclass of ActionServlet (after the super's doGet/doPost are called). ...but still the same results. We are running Struts on Sybase EAServer 4.2, by the way. Thanks in advance, Shahak Nagiel Software Engineer Northrop Grumman Mission Systems - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Compression Filter
No, the problem is that the implementation you are using is the same as the
one our programmer tried to use. In the Servlet spec, you can write to
response 2 different ways. Depending on the application server you are
using, this can be through the writer or stream, but not both. This is the
problem you are seeing.
http://java.sun.com/j2ee/1.4/docs/api/javax/servlet/ServletResponse.html#get
OutputStream()
Have your ResponseWrapper instead write to an object like this. Also, in
your filter, before you wrap, check the instanceof the response to make sure
you don't double bag the response (servlet 2.3 spec).
public class ResponseToken
{
private byte[] content;
private transient ByteArrayOutputStream outputStream = new
ByteArrayOutputStream();
public ResponseToken()
{
}
public ResponseToken(String content)
{
this.content = content.getBytes();
}
public void commit()
{
if (this.content == null)
{
try
{
this.outputStream.close();
}
catch (IOException e)
{
}
this.content = this.outputStream.toByteArray();
}
}
public OutputStream getOutputStream()
{
return outputStream;
}
public void setOutputStream(ByteArrayOutputStream outputStream)
{
this.outputStream = outputStream;
}
public void readExternal(ObjectInput input)
throws IOException, ClassNotFoundException
{
this.content = (byte[]) input.readObject();
}
public void writeExternal(ObjectOutput output) throws IOException
{
this.commit();
output.writeObject(this.content);
}
public void writeToResponse(HttpServletResponse response)
throws ServletException, IOException
{
this.commit();
OutputStream os = new
BufferedOutputStream(response.getOutputStream());
os.write(this.content);
os.flush();
}
}
Jacob Hookom
Senior Analyst/Programmer
McKesson Medical-Surgical
Golden Valley, Minnesota
http://www.mckesson.com
-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Tuesday, March 09, 2004 3:24 PM
To: [EMAIL PROTECTED]
Subject: RE: Compression Filter
Indeed, I got the exceptions you mentioned. Presumably, this is because
requests for .dos ultimately either forward or redirect to JSP's, and, I
believe, either one will flush the response buffer and hence commit the
response.
So, does this mean there's no way to enable a filter-based compression with
Struts?
-Original Message-
From: Hookom, Jacob [mailto:[EMAIL PROTECTED]
Sent: Tuesday, March 09, 2004 4:04 PM
To: Struts Users Mailing List
Subject: RE: Compression Filter
Check your server logs for exceptions that say the response has already been
committed. We had a programmer try to create a compression filter based on
the source from one of those articles and it did not work on our production
servers. Worth a look...
-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Tuesday, March 09, 2004 2:56 PM
To: [EMAIL PROTECTED]
Subject: Compression Filter
I'm trying to implement a compression filter on the HTTP response similar to
that discussed in
http://www.onjava.com/pub/a/onjava/2003/11/19/filters.html?page=1.
When requesting straight JSP's, it works fine, but any Struts .dos do not
work. Specifically, it appears the compression filter itself functions
normally, but the browser responds with an empty page. (The source code,
cryptically enough, does include htmlbody/body/html, but I suspect
that's being defaulted somewhere.)
I've tried:
- Configuring the filter to handle *.do as a url-pattern, instead of the
servlet-name action.
- Commenting out the compression code entirely, leaving only
GZIPResponseWrapper wrappedResponse = new GZIPResponseWrapper(res);
chain.doFilter(req, wrappedResponse);
- Executing the compression on a subclass of ActionServlet (after the
super's doGet/doPost are called).
...but still the same results.
We are running Struts on Sybase EAServer 4.2, by the way.
Thanks in advance,
Shahak Nagiel
Software Engineer
Northrop Grumman Mission Systems
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
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To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED
Re: Tomcat 4 Compression Filter
Thanks Navjot. Thats another option I hadn't thought of. Niall - Original Message - From: Navjot Singh [EMAIL PROTECTED] To: Struts Users Mailing List [EMAIL PROTECTED] Sent: Thursday, February 26, 2004 5:10 AM Subject: RE: Tomcat 4 Compression Filter put apache in front of tomcat and install mod_gzip with apache. it will do almost everything you can wish for? -Original Message- From: Niall Pemberton [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 5:43 PM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/exampl es/WEB-INF/classes/compressionFilters/CompressionFilter.java?rev=1. 8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Tomcat 4 Compression Filter
There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/examples/WEB-INF/classes/compressionFilters/CompressionFilter.java?rev=1.8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall
RE: Tomcat 4 Compression Filter
I've also been playing around with this with mixed results. I've been looking for some doc on the filter mainly to better understand the 'compressThreshold' setting. Does anyone have any doc for this thing? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Niall Pemberton [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 6:13 AM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/e xamples/WEB-INF/classes/compressionFilters/CompressionFilter.j ava?rev=1.8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall This transmission (and any information attached to it) may be confidential and is intended solely for the use of the individual or entity to which it is addressed. If you are not the intended recipient or the person responsible for delivering the transmission to the intended recipient, be advised that you have received this transmission in error and that any use, dissemination, forwarding, printing, or copying of this information is strictly prohibited. If you have received this transmission in error, please immediately notify LabOne at the following email address: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat 4 Compression Filter
Essentially, the compressionThreshold filter init param is a buffer size for CompressionResponseStream. If it's 0, then compression is turned off (this is handled by the filter, not the stream). Otherwise, it's the max of 128 (hard-coded min) and whatever is set in web.xml. The stream works by buffering up bytes and periodically flushing them to a GZIPOutputStream that wraps the response's ouput stream. Quoting Jerry Jalenak [EMAIL PROTECTED]: I've also been playing around with this with mixed results. I've been looking for some doc on the filter mainly to better understand the 'compressThreshold' setting. Does anyone have any doc for this thing? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Niall Pemberton [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 6:13 AM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/e xamples/WEB-INF/classes/compressionFilters/CompressionFilter.j ava?rev=1.8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall -- Kris Schneider mailto:[EMAIL PROTECTED] D.O.Tech http://www.dotech.com/ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat 4 Compression Filter
Kris - Thanks. So what's a reasonable setting? The example has the threshold set to 10; is this OK for most web apps? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Kris Schneider [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 9:42 AM To: Struts Users Mailing List Subject: RE: Tomcat 4 Compression Filter Essentially, the compressionThreshold filter init param is a buffer size for CompressionResponseStream. If it's 0, then compression is turned off (this is handled by the filter, not the stream). Otherwise, it's the max of 128 (hard-coded min) and whatever is set in web.xml. The stream works by buffering up bytes and periodically flushing them to a GZIPOutputStream that wraps the response's ouput stream. Quoting Jerry Jalenak [EMAIL PROTECTED]: I've also been playing around with this with mixed results. I've been looking for some doc on the filter mainly to better understand the 'compressThreshold' setting. Does anyone have any doc for this thing? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Niall Pemberton [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 6:13 AM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/e xamples/WEB-INF/classes/compressionFilters/CompressionFilter.j ava?rev=1.8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall -- Kris Schneider mailto:[EMAIL PROTECTED] D.O.Tech http://www.dotech.com/ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] This transmission (and any information attached to it) may be confidential and is intended solely for the use of the individual or entity to which it is addressed. If you are not the intended recipient or the person responsible for delivering the transmission to the intended recipient, be advised that you have received this transmission in error and that any use, dissemination, forwarding, printing, or copying of this information is strictly prohibited. If you have received this transmission in error, please immediately notify LabOne at the following email address: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat 4 Compression Filter
...its also what its name implies a threshold - if the reponse doesn't exceed the threshold (in bytes) it writes it out normally - uncompressed. - Original Message - From: Kris Schneider [EMAIL PROTECTED] To: Struts Users Mailing List [EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 3:41 PM Subject: RE: Tomcat 4 Compression Filter Essentially, the compressionThreshold filter init param is a buffer size for CompressionResponseStream. If it's 0, then compression is turned off (this is handled by the filter, not the stream). Otherwise, it's the max of 128 (hard-coded min) and whatever is set in web.xml. The stream works by buffering up bytes and periodically flushing them to a GZIPOutputStream that wraps the response's ouput stream. Quoting Jerry Jalenak [EMAIL PROTECTED]: I've also been playing around with this with mixed results. I've been looking for some doc on the filter mainly to better understand the 'compressThreshold' setting. Does anyone have any doc for this thing? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Niall Pemberton [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 6:13 AM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/e xamples/WEB-INF/classes/compressionFilters/CompressionFilter.j ava?rev=1.8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall -- Kris Schneider mailto:[EMAIL PROTECTED] D.O.Tech http://www.dotech.com/ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat 4 Compression Filter
If you set it less than 10, it will get re-set to 128 (unless its zero) - Original Message - From: Jerry Jalenak [EMAIL PROTECTED] To: 'Struts Users Mailing List' [EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 3:57 PM Subject: RE: Tomcat 4 Compression Filter Kris - Thanks. So what's a reasonable setting? The example has the threshold set to 10; is this OK for most web apps? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Kris Schneider [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 9:42 AM To: Struts Users Mailing List Subject: RE: Tomcat 4 Compression Filter Essentially, the compressionThreshold filter init param is a buffer size for CompressionResponseStream. If it's 0, then compression is turned off (this is handled by the filter, not the stream). Otherwise, it's the max of 128 (hard-coded min) and whatever is set in web.xml. The stream works by buffering up bytes and periodically flushing them to a GZIPOutputStream that wraps the response's ouput stream. Quoting Jerry Jalenak [EMAIL PROTECTED]: I've also been playing around with this with mixed results. I've been looking for some doc on the filter mainly to better understand the 'compressThreshold' setting. Does anyone have any doc for this thing? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Niall Pemberton [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 6:13 AM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/e xamples/WEB-INF/classes/compressionFilters/CompressionFilter.j ava?rev=1.8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall -- Kris Schneider mailto:[EMAIL PROTECTED] D.O.Tech http://www.dotech.com/ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] This transmission (and any information attached to it) may be confidential and is intended solely for the use of the individual or entity to which it is addressed. If you are not the intended recipient or the person responsible for delivering the transmission to the intended recipient, be advised that you have received this transmission in error and that any use, dissemination, forwarding, printing, or copying of this information is strictly prohibited. If you have received this transmission in error, please immediately notify LabOne at the following email address: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat 4 Compression Filter
Can you enable mod_gzip and/or mod_deflate for Apache? I've always felt that's a better deliniation of responsibilities between the servers. Rick DeBay On Wed, 25 Feb 2004 08:58 , Jerry Jalenak [EMAIL PROTECTED] sent: I've also been playing around with this with mixed results. I've been looking for some doc on the filter mainly to better understand the 'compressThreshold' setting. Does anyone have any doc for this thing? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Niall Pemberton [EMAIL PROTECTED]','','','')[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 6:13 AM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/e xamples/WEB-INF/classes/compressionFilters/CompressionFilter.j ava?rev=1.8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall This transmission (and any information attached to it) may be confidential and is intended solely for the use of the individual or entity to which it is addressed. If you are not the intended recipient or the person responsible for delivering the transmission to the intended recipient, be advised that you have received this transmission in error and that any use, dissemination, forwarding, printing, or copying of this information is strictly prohibited. If you have received this transmission in error, please immediately notify LabOne at the following email address: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat 4 Compression Filter
I wouldn't compress anything less than a packet. A good minimum packet size is 576 bytes, so call it 512 to account for headers and to make it even. I'd still use Apache and mod_gzip/mod_deflate as that will make caching proxies much happier. Rick DeBay On Wed, 25 Feb 2004 09:57 , Jerry Jalenak [EMAIL PROTECTED] sent: Kris - Thanks. So what's a reasonable setting? The example has the threshold set to 10; is this OK for most web apps? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Kris Schneider [EMAIL PROTECTED]','','','')[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 9:42 AM To: Struts Users Mailing List Subject: RE: Tomcat 4 Compression Filter Essentially, the compressionThreshold filter init param is a buffer size for CompressionResponseStream. If it's 0, then compression is turned off (this is handled by the filter, not the stream). Otherwise, it's the max of 128 (hard-coded min) and whatever is set in web.xml. The stream works by buffering up bytes and periodically flushing them to a GZIPOutputStream that wraps the response's ouput stream. Quoting Jerry Jalenak [EMAIL PROTECTED]: I've also been playing around with this with mixed results. I've been looking for some doc on the filter mainly to better understand the 'compressThreshold' setting. Does anyone have any doc for this thing? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Niall Pemberton [EMAIL PROTECTED]','','','')[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 6:13 AM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/e xamples/WEB-INF/classes/compressionFilters/CompressionFilter.j ava?rev=1.8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall -- Kris Schneider [EMAIL PROTECTED]','','','')[EMAIL PROTECTED] D.O.Tech http://www.dotech.com/ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] This transmission (and any information attached to it) may be confidential and is intended solely for the use of the individual or entity to which it is addressed. If you are not the intended recipient or the person responsible for delivering the transmission to the intended recipient, be advised that you have received this transmission in error and that any use, dissemination, forwarding, printing, or copying of this information is strictly prohibited. If you have received this transmission in error, please immediately notify LabOne at the following email address: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat 4 Compression Filter
It should probably also be mentioned that the JSP buffer can play a role in how this thing works. The page implementation will generally have a buffer of its own, the default size for JSP 1.2 is at least 8KB (it can be changed with the page directive). If the page implementation writes a buffer whose content length is greater than the compression stream's buffer size, then the page's buffer will be written directly to the GZIP stream. Quoting Niall Pemberton [EMAIL PROTECTED]: If you set it less than 10, it will get re-set to 128 (unless its zero) - Original Message - From: Jerry Jalenak [EMAIL PROTECTED] To: 'Struts Users Mailing List' [EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 3:57 PM Subject: RE: Tomcat 4 Compression Filter Kris - Thanks. So what's a reasonable setting? The example has the threshold set to 10; is this OK for most web apps? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Kris Schneider [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 9:42 AM To: Struts Users Mailing List Subject: RE: Tomcat 4 Compression Filter Essentially, the compressionThreshold filter init param is a buffer size for CompressionResponseStream. If it's 0, then compression is turned off (this is handled by the filter, not the stream). Otherwise, it's the max of 128 (hard-coded min) and whatever is set in web.xml. The stream works by buffering up bytes and periodically flushing them to a GZIPOutputStream that wraps the response's ouput stream. Quoting Jerry Jalenak [EMAIL PROTECTED]: I've also been playing around with this with mixed results. I've been looking for some doc on the filter mainly to better understand the 'compressThreshold' setting. Does anyone have any doc for this thing? Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] -Original Message- From: Niall Pemberton [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 6:13 AM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/e xamples/WEB-INF/classes/compressionFilters/CompressionFilter.j ava?rev=1.8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall -- Kris Schneider mailto:[EMAIL PROTECTED] D.O.Tech http://www.dotech.com/ -- Kris Schneider mailto:[EMAIL PROTECTED] D.O.Tech http://www.dotech.com/ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat 4 Compression Filter
On Wednesday 25 February 2004 15:58, Jerry Jalenak wrote: I've also been playing around with this with mixed results. I've been looking for some doc on the filter mainly to better understand the 'compressThreshold' setting. Does anyone have any doc for this thing? IIRC the 4.x filter used to be rather undocumented, but you can easily tell what it does by looking at the sources. Two things I may note is that 1.) compressing anything else than text/html or text/plain may show unsatisfactory results; some things just don't work at all when using compression (VCARDs, for example) 2. IIRC there is a memory leak issue with the GZip packages in some Java versions, so it's a good idea to do proper load testing before going live. One option for high-volume sites is to set up a dedicated 'compression server' which does the job, and that one doesn't necessarily have to run Java. Generally, compression can easily speed up page delivery by factor 4 (if the browser understands GZIP, which IE and recent Mozilla versions do, at least), but you have to weigh this benefit against the additional overhead imposed on the server side. BTW, IMHO the TC 4.x filter's built in compression minimum threshold of 128K is way too big (with pages being that big: don't forget the buffer); most pages are smaller, and the performance boost hooks in at smaller file sizes as well. 32KB might be a good starting point for further explorations in this direction. HTH, -- Chris. Jerry Jalenak Development Manager, Web Publishing LabOne, Inc. 10101 Renner Blvd. Lenexa, KS 66219 (913) 577-1496 [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat 4 Compression Filter
put apache in front of tomcat and install mod_gzip with apache. it will do almost everything you can wish for? -Original Message- From: Niall Pemberton [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 25, 2004 5:43 PM To: Struts User Jakarta Subject: Tomcat 4 Compression Filter There is a CompressionFilter class shipped with with Tomcat which compresses the ServletResponse that I'm considering using (we have some remote offices which have slow links): http://cvs.apache.org/viewcvs.cgi/jakarta-tomcat-4.0/webapps/exampl es/WEB-INF/classes/compressionFilters/CompressionFilter.java?rev=1. 8view=auto It looks OK to me and seems to work fine when I plug it into my app. I'm a bit concerned that its only an example class rather than standard feature of Tomcat. Has anyone used this in a 'live' environment and if so are there any issues or with it or recommendations? Does anyone have any alternatives that they have deployed? Niall - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Anyone using the compression filter from Tomcat 4.0 examples?
Hi all, Has anyone implemented the compression filter contributed by Amy Roh from Sun to the Tomcat 4.0 examples Web application.? The filter automatically compresses the response output stream, improving bandwidth utilization. As documented in Jason Hunter's article for javaworld: http://www.javaworld.com/javaworld/jw-06-2001/jw-0622-filters-p3.html The strategy of the CompressionFilter class is to examine the request headers to determine if the client supports compression, and if so, wrap the response object with a custom response whose getOutputStream() and getWriter() methods have been customized to utilize a compressed output stream. I have it up and running in my development environment and haven't experienced any problems! Which is great! I want to feel confident prior to releasing my app to Production, that there aren't any known problems waiting for me. Has anyone experienced problems using it in production? Does the actual compression take too long for anyone? Did it prove to be a bottleneck for anyone? Basically have people found this compression filter to be beneficial or detrimental? I'm always looking for ways to improving bandwidth utilization. I'm just not sure what benefits the compression filter really give me - I searched the struts-users list and found little debate regarding this filter. TIA, Mike
