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Posted to modules-dev@httpd.apache.org by Niko Goutte <ng...@hotmail.com> on 2011/03/31 14:32:39 UTC
cpu 100%
Hello,
I developped an apache module which send small data coming from file.
A client request from file through a Get request and data are sent with block
size equals to 100KB.
One 100KB buffer is allocated in the pool, then each buffer are used to create
one bucket that will be sent just after being inserted into the brigade.
To sum up:
----------------------------------------------------------------------------------------------------------------------------
apr_bucket_brigade *bb;
apr_bucket* b;
bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
Buf = apr_palloc(r->pool,100KB);
while(lastBufferToSend==false)
{
Processing(Buf);
b = apr_bucket_pool_create(Buf ,size, r->pool, r->connection->bucket_alloc) ;
APR_BRIGADE_INSERT_TAIL(bb, b);
APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_flush_create(bb->bucket_alloc));
if(lastBufferToSend)
{
APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_eos_create(bb->bucket_alloc));
}
rv = ap_pass_brigade(r->output_filters, bb);
if (rv != APR_SUCCESS)
{
return HTTP_INTERNAL_SERVER_ERROR;
}
apr_brigade_cleanup(bb);
}
apr_brigade_destroy(bb);
----------------------------------------------------------------------------------------------------------------------------
I want to call ap_pass_brigade for each buffer because I want the module to
send immediatly 100KB.
Clients don't have to wait for the complete processing of the file more than
2GB. They receive small blocks until the end.
--------------------------------------------------------------------------------------------------------------------------
Apache Server is in prefork mode.
<IfModule prefork.c>
StartServers 8
MinSpareServers 5
MaxSpareServers 20
ServerLimit 256
MaxClients 256
MaxRequestsPerChild 4000
</IfModule>
In worker mode, everything is excepted 10 bytes that are send in addition including value
"\n256\r\n" : it is very strange because the sum of every chunk corrsesponds exactly to the expected size.
<IfModule worker.c>
StartServers 2
MinSpareThreads 25
MaxSpareThreads 75
ThreadPerChild 64
MaxClients 1024
MaxRequestsPerChild 0
</IfModule>
--------------------------------------------------------------------------------------------------------------------------
MY PROBLEMS:
In prefork mode, the first 8 client requests (which corresponds to the StartServers = 8) are well processed. My client received all data, everything is fine.
But the 9th freezes the module in ap_pass_brigade function. httpd is freezed with 100% cpu on this process.
In worker mode, it is ok excepted the 10 bytes added. It seems that it is linked with apr_brigade_destroy or apr_bucket_delete(b).
If someone can provide me answers to these problems, I'll be very happy.
Thank you.
Nicolas.
RE: cpu 100%
Posted by Niko Goutte <ng...@hotmail.com>.
> Date: Thu, 31 Mar 2011 19:25:58 +0200
> Subject: Re: cpu 100%
> From: sorinm@gmail.com
> To: modules-dev@httpd.apache.org
>
> On Thu, Mar 31, 2011 at 19:10, Niko Goutte <ng...@hotmail.com> wrote:
> >
> >> Date: Thu, 31 Mar 2011 18:22:34 +0200
> >> Subject: Re: cpu 100%
> >> From: sorinm@gmail.com
> >> To: modules-dev@httpd.apache.org
> >>
> >> > -------------------------------------------------------------------------------------------------------------------------------
> >> > HERE IS:
> >> > #include <httpd.h>
> >> > #include <http_config.h>
> >> > #include <http_protocol.h>
> >> > #include <http_request.h>
> >> > #include <http_log.h>
> >> > #include <ap_compat.h>
> >> > #include <apr_buckets.h>
> >> > #include <apr_strings.h>
> >> >
> >> >
> >> > #define ASE_FILE_SIZE 512000
> >> > #define ASE_BUFFER_SIZE 104858
> >> >
> >> > module AP_MODULE_DECLARE_DATA ase_mod_module;
> >> > #define ASE_MOD_HANDLER "ase-mod.extensions"
> >> >
> >> > static int ase_mod_handler(request_rec *r)
> >> > {
> >> > apr_status_t rv = APR_SUCCESS;
> >> > apr_bucket_brigade* bb = NULL;;
> >> > apr_bucket* b = NULL;;
> >> > char filename[256];
> >> >
> >> > /* First, some housekeeping. */
> >> > if (((!r->handler) != 0)|| (strcmp(r->handler, ASE_MOD_HANDLER)))
> >> > {
> >> > /* r->handler wasn't "ase_mod", so it's none of our business */
> >> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Decline processing file %s is not %s and handler %s", r->filename,ASE_MOD_HANDLER,r->handler);
> >> > return DECLINED;
> >> > }
> >> >
> >> > if (r->method_number != M_GET)
> >> > {
> >> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Error METHOD_NOT_ALLOWED (%d)",r->method_number);
> >> > return HTTP_METHOD_NOT_ALLOWED;
> >> > }
> >> >
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"%s",r->the_request);
> >> >
> >> > // Construct filename
> >> > strncpy(filename, r->filename, sizeof(filename) / sizeof(char) - 1);
> >> > filename[sizeof(filename) / sizeof(char) - 1] = '\0';
> >> >
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"filename = %s",filename);
> >> >
> >> > int DataSize = ASE_FILE_SIZE;
> >> >
> >> > ap_set_content_type(r, "video/ase");
> >> >
> >> > ap_update_mtime(r, r->finfo.mtime);
> >> > ap_set_last_modified(r);
> >> >
> >> > apr_table_setn(r->headers_out, "Accept-Ranges", "bytes");
> >> >
> >> > r->vlist_validator = apr_pstrcat(r->pool, "X",apr_itoa(r->pool, DataSize), "\"", NULL);
> >> > ap_set_etag(r);
> >> >
> >> > char content_range[64];
> >> > sprintf(content_range,"bytes %d-%d/%d",0,ASE_FILE_SIZE-1,ASE_FILE_SIZE);
> >> > ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,"Add content range %s",content_range);
> >> > apr_table_setn(r->headers_out, "Content-Range",content_range);
> >> >
> >> > r->status = HTTP_OK;
> >> >
> >> > bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
> >> > char* Buf;
> >> > Buf = apr_palloc(r->pool,ASE_BUFFER_SIZE);
> >> > int size = ASE_BUFFER_SIZE;
> >> >
> >> > unsigned int count = 0;
> >> > while(DataSize>0)
> >> > {
> >> > if((DataSize - size)<0)
> >> > {
> >> > size = DataSize;
> >> > }
> >> >
> >> > memset(Buf,count,size);
> >> >
> >> > b = apr_bucket_pool_create(Buf ,size, r->pool, r->connection->bucket_alloc) ;
> >> >
> >> > APR_BRIGADE_INSERT_TAIL(bb, b);
> >> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_flush_create(bb->bucket_alloc));
> >> >
> >> > if(DataSize <= size)
> >> > {
> >> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_eos_create(bb->bucket_alloc));
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"APR_BRIGADE_INSERT_TAIL EOS Bucket");
> >> > }
> >> >
> >> > rv = ap_pass_brigade(r->output_filters, bb);
> >> >
> >> > if (rv != APR_SUCCESS)
> >> > {
> >> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"HTTP_INTERNAL_SERVER_ERROR ap_pass_brigade ");
> >> > r->status = HTTP_INTERNAL_SERVER_ERROR;
> >> > return r->status;
> >> > }
> >> >
> >> > DataSize = DataSize - size;
> >> > count++;
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"ap_pass_brigade, DataSize = %d and Size = %d",DataSize, size );
> >> >
> >> > apr_brigade_cleanup(bb);
> >> > }
> >> >
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"Out of While");
> >> >
> >> > apr_bucket_delete(b);
> >>
> >> Try to remove this apr_bucket_delete from here. apr_brigade_cleanup in
> >> the while loop deletes the buckets in the brigade. I think you delete
> >> b twice.
> >>
> >> Sorin
> >
> >
> >
> > That's true, I've no more the segmentation fault but in wireshark capture on the client side, I've this error message only in prefork mode:
> >
> >
> >
> > GET /mmrk_dummy_2mbps_10s.mmrk?TxId=8 HTTP/1.1
> > Range: bytes=0-511999
> > User-Agent: curl/7.15.5 (x86_64-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5
> > Host: 192.X.X.X
> >
> > Accept: */*
> > Cache-Control: no-cache
> >
> > HTTP/1.1 200 OK
> > Date: Thu, 31 Mar 2011 16:53:57 GMT
> > Server: Apache/2.2.3 (CentOS)
> > Last-Modified: Fri, 25 Mar 2011 11:18:16 GMT
> > Accept-Ranges: bytes
> > ETag: "12a8006-4e2e90-49f4cc0186e00;512000"
> > Content-Range: bytes 0-511999/512000
> > Connection: close
> > Transfer-Encoding: chunked
> > Content-Type: video/ase
> >
> > 1999a + DATA
> > 1999a + DATA
> > 1999a + DATA
> > 1999a + DATA
> > 0
> >
> > 23e
> > <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
> > <html><head>
> > <title>200 OK</title>
> > </head><body>
> > <h1>OK</h1>
> > <p>The server encountered an internal error or
> > misconfiguration and was unable to complete
> > your request.</p>
> > <p>Please contact the server administrator,
> > root@localhost and inform them of the time the error occurred,
> > and anything you might have done that may have
> > caused the error.</p>
> > <p>More information about this error may be available
> > in the server error log.</p>
> > <hr>
> > <address>Apache/2.2.3 (CentOS) Server at 192.X.X.X Port 80</address>
> > </body></html>
> >
>
> Try to exit with return OK instead of return r->status from your handler.
>
> Sorin
Well done !!
It works fine now.
Thank you.
Nicolas.
RE: cpu 100%
Posted by Niko Goutte <ng...@hotmail.com>.
> Date: Thu, 31 Mar 2011 19:25:58 +0200
> Subject: Re: cpu 100%
> From: sorinm@gmail.com
> To: modules-dev@httpd.apache.org
>
> On Thu, Mar 31, 2011 at 19:10, Niko Goutte <ng...@hotmail.com> wrote:
> >
> >> Date: Thu, 31 Mar 2011 18:22:34 +0200
> >> Subject: Re: cpu 100%
> >> From: sorinm@gmail.com
> >> To: modules-dev@httpd.apache.org
> >>
> >> > -------------------------------------------------------------------------------------------------------------------------------
> >> > HERE IS:
> >> > #include <httpd.h>
> >> > #include <http_config.h>
> >> > #include <http_protocol.h>
> >> > #include <http_request.h>
> >> > #include <http_log.h>
> >> > #include <ap_compat.h>
> >> > #include <apr_buckets.h>
> >> > #include <apr_strings.h>
> >> >
> >> >
> >> > #define ASE_FILE_SIZE 512000
> >> > #define ASE_BUFFER_SIZE 104858
> >> >
> >> > module AP_MODULE_DECLARE_DATA ase_mod_module;
> >> > #define ASE_MOD_HANDLER "ase-mod.extensions"
> >> >
> >> > static int ase_mod_handler(request_rec *r)
> >> > {
> >> > apr_status_t rv = APR_SUCCESS;
> >> > apr_bucket_brigade* bb = NULL;;
> >> > apr_bucket* b = NULL;;
> >> > char filename[256];
> >> >
> >> > /* First, some housekeeping. */
> >> > if (((!r->handler) != 0)|| (strcmp(r->handler, ASE_MOD_HANDLER)))
> >> > {
> >> > /* r->handler wasn't "ase_mod", so it's none of our business */
> >> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Decline processing file %s is not %s and handler %s", r->filename,ASE_MOD_HANDLER,r->handler);
> >> > return DECLINED;
> >> > }
> >> >
> >> > if (r->method_number != M_GET)
> >> > {
> >> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Error METHOD_NOT_ALLOWED (%d)",r->method_number);
> >> > return HTTP_METHOD_NOT_ALLOWED;
> >> > }
> >> >
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"%s",r->the_request);
> >> >
> >> > // Construct filename
> >> > strncpy(filename, r->filename, sizeof(filename) / sizeof(char) - 1);
> >> > filename[sizeof(filename) / sizeof(char) - 1] = '\0';
> >> >
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"filename = %s",filename);
> >> >
> >> > int DataSize = ASE_FILE_SIZE;
> >> >
> >> > ap_set_content_type(r, "video/ase");
> >> >
> >> > ap_update_mtime(r, r->finfo.mtime);
> >> > ap_set_last_modified(r);
> >> >
> >> > apr_table_setn(r->headers_out, "Accept-Ranges", "bytes");
> >> >
> >> > r->vlist_validator = apr_pstrcat(r->pool, "X",apr_itoa(r->pool, DataSize), "\"", NULL);
> >> > ap_set_etag(r);
> >> >
> >> > char content_range[64];
> >> > sprintf(content_range,"bytes %d-%d/%d",0,ASE_FILE_SIZE-1,ASE_FILE_SIZE);
> >> > ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,"Add content range %s",content_range);
> >> > apr_table_setn(r->headers_out, "Content-Range",content_range);
> >> >
> >> > r->status = HTTP_OK;
> >> >
> >> > bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
> >> > char* Buf;
> >> > Buf = apr_palloc(r->pool,ASE_BUFFER_SIZE);
> >> > int size = ASE_BUFFER_SIZE;
> >> >
> >> > unsigned int count = 0;
> >> > while(DataSize>0)
> >> > {
> >> > if((DataSize - size)<0)
> >> > {
> >> > size = DataSize;
> >> > }
> >> >
> >> > memset(Buf,count,size);
> >> >
> >> > b = apr_bucket_pool_create(Buf ,size, r->pool, r->connection->bucket_alloc) ;
> >> >
> >> > APR_BRIGADE_INSERT_TAIL(bb, b);
> >> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_flush_create(bb->bucket_alloc));
> >> >
> >> > if(DataSize <= size)
> >> > {
> >> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_eos_create(bb->bucket_alloc));
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"APR_BRIGADE_INSERT_TAIL EOS Bucket");
> >> > }
> >> >
> >> > rv = ap_pass_brigade(r->output_filters, bb);
> >> >
> >> > if (rv != APR_SUCCESS)
> >> > {
> >> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"HTTP_INTERNAL_SERVER_ERROR ap_pass_brigade ");
> >> > r->status = HTTP_INTERNAL_SERVER_ERROR;
> >> > return r->status;
> >> > }
> >> >
> >> > DataSize = DataSize - size;
> >> > count++;
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"ap_pass_brigade, DataSize = %d and Size = %d",DataSize, size );
> >> >
> >> > apr_brigade_cleanup(bb);
> >> > }
> >> >
> >> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"Out of While");
> >> >
> >> > apr_bucket_delete(b);
> >>
> >> Try to remove this apr_bucket_delete from here. apr_brigade_cleanup in
> >> the while loop deletes the buckets in the brigade. I think you delete
> >> b twice.
> >>
> >> Sorin
> >
> >
> >
> > That's true, I've no more the segmentation fault but in wireshark capture on the client side, I've this error message only in prefork mode:
> >
> >
> >
> > GET /mmrk_dummy_2mbps_10s.mmrk?TxId=8 HTTP/1.1
> > Range: bytes=0-511999
> > User-Agent: curl/7.15.5 (x86_64-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5
> > Host: 192.X.X.X
> >
> > Accept: */*
> > Cache-Control: no-cache
> >
> > HTTP/1.1 200 OK
> > Date: Thu, 31 Mar 2011 16:53:57 GMT
> > Server: Apache/2.2.3 (CentOS)
> > Last-Modified: Fri, 25 Mar 2011 11:18:16 GMT
> > Accept-Ranges: bytes
> > ETag: "12a8006-4e2e90-49f4cc0186e00;512000"
> > Content-Range: bytes 0-511999/512000
> > Connection: close
> > Transfer-Encoding: chunked
> > Content-Type: video/ase
> >
> > 1999a + DATA
> > 1999a + DATA
> > 1999a + DATA
> > 1999a + DATA
> > 0
> >
> > 23e
> > <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
> > <html><head>
> > <title>200 OK</title>
> > </head><body>
> > <h1>OK</h1>
> > <p>The server encountered an internal error or
> > misconfiguration and was unable to complete
> > your request.</p>
> > <p>Please contact the server administrator,
> > root@localhost and inform them of the time the error occurred,
> > and anything you might have done that may have
> > caused the error.</p>
> > <p>More information about this error may be available
> > in the server error log.</p>
> > <hr>
> > <address>Apache/2.2.3 (CentOS) Server at 192.X.X.X Port 80</address>
> > </body></html>
> >
>
> Try to exit with return OK instead of return r->status from your handler.
>
> Sorin
Well done !!
It works fine now.
Thank you.
Re: cpu 100%
Posted by Sorin Manolache <so...@gmail.com>.
On Thu, Mar 31, 2011 at 19:10, Niko Goutte <ng...@hotmail.com> wrote:
>
>> Date: Thu, 31 Mar 2011 18:22:34 +0200
>> Subject: Re: cpu 100%
>> From: sorinm@gmail.com
>> To: modules-dev@httpd.apache.org
>>
>> > -------------------------------------------------------------------------------------------------------------------------------
>> > HERE IS:
>> > #include <httpd.h>
>> > #include <http_config.h>
>> > #include <http_protocol.h>
>> > #include <http_request.h>
>> > #include <http_log.h>
>> > #include <ap_compat.h>
>> > #include <apr_buckets.h>
>> > #include <apr_strings.h>
>> >
>> >
>> > #define ASE_FILE_SIZE 512000
>> > #define ASE_BUFFER_SIZE 104858
>> >
>> > module AP_MODULE_DECLARE_DATA ase_mod_module;
>> > #define ASE_MOD_HANDLER "ase-mod.extensions"
>> >
>> > static int ase_mod_handler(request_rec *r)
>> > {
>> > apr_status_t rv = APR_SUCCESS;
>> > apr_bucket_brigade* bb = NULL;;
>> > apr_bucket* b = NULL;;
>> > char filename[256];
>> >
>> > /* First, some housekeeping. */
>> > if (((!r->handler) != 0)|| (strcmp(r->handler, ASE_MOD_HANDLER)))
>> > {
>> > /* r->handler wasn't "ase_mod", so it's none of our business */
>> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Decline processing file %s is not %s and handler %s", r->filename,ASE_MOD_HANDLER,r->handler);
>> > return DECLINED;
>> > }
>> >
>> > if (r->method_number != M_GET)
>> > {
>> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Error METHOD_NOT_ALLOWED (%d)",r->method_number);
>> > return HTTP_METHOD_NOT_ALLOWED;
>> > }
>> >
>> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"%s",r->the_request);
>> >
>> > // Construct filename
>> > strncpy(filename, r->filename, sizeof(filename) / sizeof(char) - 1);
>> > filename[sizeof(filename) / sizeof(char) - 1] = '\0';
>> >
>> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"filename = %s",filename);
>> >
>> > int DataSize = ASE_FILE_SIZE;
>> >
>> > ap_set_content_type(r, "video/ase");
>> >
>> > ap_update_mtime(r, r->finfo.mtime);
>> > ap_set_last_modified(r);
>> >
>> > apr_table_setn(r->headers_out, "Accept-Ranges", "bytes");
>> >
>> > r->vlist_validator = apr_pstrcat(r->pool, "X",apr_itoa(r->pool, DataSize), "\"", NULL);
>> > ap_set_etag(r);
>> >
>> > char content_range[64];
>> > sprintf(content_range,"bytes %d-%d/%d",0,ASE_FILE_SIZE-1,ASE_FILE_SIZE);
>> > ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,"Add content range %s",content_range);
>> > apr_table_setn(r->headers_out, "Content-Range",content_range);
>> >
>> > r->status = HTTP_OK;
>> >
>> > bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
>> > char* Buf;
>> > Buf = apr_palloc(r->pool,ASE_BUFFER_SIZE);
>> > int size = ASE_BUFFER_SIZE;
>> >
>> > unsigned int count = 0;
>> > while(DataSize>0)
>> > {
>> > if((DataSize - size)<0)
>> > {
>> > size = DataSize;
>> > }
>> >
>> > memset(Buf,count,size);
>> >
>> > b = apr_bucket_pool_create(Buf ,size, r->pool, r->connection->bucket_alloc) ;
>> >
>> > APR_BRIGADE_INSERT_TAIL(bb, b);
>> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_flush_create(bb->bucket_alloc));
>> >
>> > if(DataSize <= size)
>> > {
>> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_eos_create(bb->bucket_alloc));
>> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"APR_BRIGADE_INSERT_TAIL EOS Bucket");
>> > }
>> >
>> > rv = ap_pass_brigade(r->output_filters, bb);
>> >
>> > if (rv != APR_SUCCESS)
>> > {
>> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"HTTP_INTERNAL_SERVER_ERROR ap_pass_brigade ");
>> > r->status = HTTP_INTERNAL_SERVER_ERROR;
>> > return r->status;
>> > }
>> >
>> > DataSize = DataSize - size;
>> > count++;
>> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"ap_pass_brigade, DataSize = %d and Size = %d",DataSize, size );
>> >
>> > apr_brigade_cleanup(bb);
>> > }
>> >
>> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"Out of While");
>> >
>> > apr_bucket_delete(b);
>>
>> Try to remove this apr_bucket_delete from here. apr_brigade_cleanup in
>> the while loop deletes the buckets in the brigade. I think you delete
>> b twice.
>>
>> Sorin
>
>
>
> That's true, I've no more the segmentation fault but in wireshark capture on the client side, I've this error message only in prefork mode:
>
>
>
> GET /mmrk_dummy_2mbps_10s.mmrk?TxId=8 HTTP/1.1
> Range: bytes=0-511999
> User-Agent: curl/7.15.5 (x86_64-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5
> Host: 192.X.X.X
>
> Accept: */*
> Cache-Control: no-cache
>
> HTTP/1.1 200 OK
> Date: Thu, 31 Mar 2011 16:53:57 GMT
> Server: Apache/2.2.3 (CentOS)
> Last-Modified: Fri, 25 Mar 2011 11:18:16 GMT
> Accept-Ranges: bytes
> ETag: "12a8006-4e2e90-49f4cc0186e00;512000"
> Content-Range: bytes 0-511999/512000
> Connection: close
> Transfer-Encoding: chunked
> Content-Type: video/ase
>
> 1999a + DATA
> 1999a + DATA
> 1999a + DATA
> 1999a + DATA
> 0
>
> 23e
> <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
> <html><head>
> <title>200 OK</title>
> </head><body>
> <h1>OK</h1>
> <p>The server encountered an internal error or
> misconfiguration and was unable to complete
> your request.</p>
> <p>Please contact the server administrator,
> root@localhost and inform them of the time the error occurred,
> and anything you might have done that may have
> caused the error.</p>
> <p>More information about this error may be available
> in the server error log.</p>
> <hr>
> <address>Apache/2.2.3 (CentOS) Server at 192.X.X.X Port 80</address>
> </body></html>
>
Try to exit with return OK instead of return r->status from your handler.
Sorin
RE: cpu 100%
Posted by Niko Goutte <ng...@hotmail.com>.
> Date: Thu, 31 Mar 2011 18:22:34 +0200
> Subject: Re: cpu 100%
> From: sorinm@gmail.com
> To: modules-dev@httpd.apache.org
>
> > -------------------------------------------------------------------------------------------------------------------------------
> > HERE IS:
> > #include <httpd.h>
> > #include <http_config.h>
> > #include <http_protocol.h>
> > #include <http_request.h>
> > #include <http_log.h>
> > #include <ap_compat.h>
> > #include <apr_buckets.h>
> > #include <apr_strings.h>
> >
> >
> > #define ASE_FILE_SIZE 512000
> > #define ASE_BUFFER_SIZE 104858
> >
> > module AP_MODULE_DECLARE_DATA ase_mod_module;
> > #define ASE_MOD_HANDLER "ase-mod.extensions"
> >
> > static int ase_mod_handler(request_rec *r)
> > {
> > apr_status_t rv = APR_SUCCESS;
> > apr_bucket_brigade* bb = NULL;;
> > apr_bucket* b = NULL;;
> > char filename[256];
> >
> > /* First, some housekeeping. */
> > if (((!r->handler) != 0)|| (strcmp(r->handler, ASE_MOD_HANDLER)))
> > {
> > /* r->handler wasn't "ase_mod", so it's none of our business */
> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Decline processing file %s is not %s and handler %s", r->filename,ASE_MOD_HANDLER,r->handler);
> > return DECLINED;
> > }
> >
> > if (r->method_number != M_GET)
> > {
> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Error METHOD_NOT_ALLOWED (%d)",r->method_number);
> > return HTTP_METHOD_NOT_ALLOWED;
> > }
> >
> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"%s",r->the_request);
> >
> > // Construct filename
> > strncpy(filename, r->filename, sizeof(filename) / sizeof(char) - 1);
> > filename[sizeof(filename) / sizeof(char) - 1] = '\0';
> >
> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"filename = %s",filename);
> >
> > int DataSize = ASE_FILE_SIZE;
> >
> > ap_set_content_type(r, "video/ase");
> >
> > ap_update_mtime(r, r->finfo.mtime);
> > ap_set_last_modified(r);
> >
> > apr_table_setn(r->headers_out, "Accept-Ranges", "bytes");
> >
> > r->vlist_validator = apr_pstrcat(r->pool, "X",apr_itoa(r->pool, DataSize), "\"", NULL);
> > ap_set_etag(r);
> >
> > char content_range[64];
> > sprintf(content_range,"bytes %d-%d/%d",0,ASE_FILE_SIZE-1,ASE_FILE_SIZE);
> > ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,"Add content range %s",content_range);
> > apr_table_setn(r->headers_out, "Content-Range",content_range);
> >
> > r->status = HTTP_OK;
> >
> > bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
> > char* Buf;
> > Buf = apr_palloc(r->pool,ASE_BUFFER_SIZE);
> > int size = ASE_BUFFER_SIZE;
> >
> > unsigned int count = 0;
> > while(DataSize>0)
> > {
> > if((DataSize - size)<0)
> > {
> > size = DataSize;
> > }
> >
> > memset(Buf,count,size);
> >
> > b = apr_bucket_pool_create(Buf ,size, r->pool, r->connection->bucket_alloc) ;
> >
> > APR_BRIGADE_INSERT_TAIL(bb, b);
> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_flush_create(bb->bucket_alloc));
> >
> > if(DataSize <= size)
> > {
> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_eos_create(bb->bucket_alloc));
> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"APR_BRIGADE_INSERT_TAIL EOS Bucket");
> > }
> >
> > rv = ap_pass_brigade(r->output_filters, bb);
> >
> > if (rv != APR_SUCCESS)
> > {
> > ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"HTTP_INTERNAL_SERVER_ERROR ap_pass_brigade ");
> > r->status = HTTP_INTERNAL_SERVER_ERROR;
> > return r->status;
> > }
> >
> > DataSize = DataSize - size;
> > count++;
> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"ap_pass_brigade, DataSize = %d and Size = %d",DataSize, size );
> >
> > apr_brigade_cleanup(bb);
> > }
> >
> > ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"Out of While");
> >
> > apr_bucket_delete(b);
>
> Try to remove this apr_bucket_delete from here. apr_brigade_cleanup in
> the while loop deletes the buckets in the brigade. I think you delete
> b twice.
>
> Sorin
That's true, I've no more the segmentation fault but in wireshark capture on the client side, I've this error message only in prefork mode:
GET /mmrk_dummy_2mbps_10s.mmrk?TxId=8 HTTP/1.1
Range: bytes=0-511999
User-Agent: curl/7.15.5 (x86_64-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5
Host: 192.X.X.X
Accept: */*
Cache-Control: no-cache
HTTP/1.1 200 OK
Date: Thu, 31 Mar 2011 16:53:57 GMT
Server: Apache/2.2.3 (CentOS)
Last-Modified: Fri, 25 Mar 2011 11:18:16 GMT
Accept-Ranges: bytes
ETag: "12a8006-4e2e90-49f4cc0186e00;512000"
Content-Range: bytes 0-511999/512000
Connection: close
Transfer-Encoding: chunked
Content-Type: video/ase
1999a + DATA
1999a + DATA
1999a + DATA
1999a + DATA
0
23e
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>200 OK</title>
</head><body>
<h1>OK</h1>
<p>The server encountered an internal error or
misconfiguration and was unable to complete
your request.</p>
<p>Please contact the server administrator,
root@localhost and inform them of the time the error occurred,
and anything you might have done that may have
caused the error.</p>
<p>More information about this error may be available
in the server error log.</p>
<hr>
<address>Apache/2.2.3 (CentOS) Server at 192.X.X.X Port 80</address>
</body></html>
0
Re: cpu 100%
Posted by Sorin Manolache <so...@gmail.com>.
> -------------------------------------------------------------------------------------------------------------------------------
> HERE IS:
> #include <httpd.h>
> #include <http_config.h>
> #include <http_protocol.h>
> #include <http_request.h>
> #include <http_log.h>
> #include <ap_compat.h>
> #include <apr_buckets.h>
> #include <apr_strings.h>
>
>
> #define ASE_FILE_SIZE 512000
> #define ASE_BUFFER_SIZE 104858
>
> module AP_MODULE_DECLARE_DATA ase_mod_module;
> #define ASE_MOD_HANDLER "ase-mod.extensions"
>
> static int ase_mod_handler(request_rec *r)
> {
> apr_status_t rv = APR_SUCCESS;
> apr_bucket_brigade* bb = NULL;;
> apr_bucket* b = NULL;;
> char filename[256];
>
> /* First, some housekeeping. */
> if (((!r->handler) != 0)|| (strcmp(r->handler, ASE_MOD_HANDLER)))
> {
> /* r->handler wasn't "ase_mod", so it's none of our business */
> ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Decline processing file %s is not %s and handler %s", r->filename,ASE_MOD_HANDLER,r->handler);
> return DECLINED;
> }
>
> if (r->method_number != M_GET)
> {
> ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Error METHOD_NOT_ALLOWED (%d)",r->method_number);
> return HTTP_METHOD_NOT_ALLOWED;
> }
>
> ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"%s",r->the_request);
>
> // Construct filename
> strncpy(filename, r->filename, sizeof(filename) / sizeof(char) - 1);
> filename[sizeof(filename) / sizeof(char) - 1] = '\0';
>
> ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"filename = %s",filename);
>
> int DataSize = ASE_FILE_SIZE;
>
> ap_set_content_type(r, "video/ase");
>
> ap_update_mtime(r, r->finfo.mtime);
> ap_set_last_modified(r);
>
> apr_table_setn(r->headers_out, "Accept-Ranges", "bytes");
>
> r->vlist_validator = apr_pstrcat(r->pool, "X",apr_itoa(r->pool, DataSize), "\"", NULL);
> ap_set_etag(r);
>
> char content_range[64];
> sprintf(content_range,"bytes %d-%d/%d",0,ASE_FILE_SIZE-1,ASE_FILE_SIZE);
> ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,"Add content range %s",content_range);
> apr_table_setn(r->headers_out, "Content-Range",content_range);
>
> r->status = HTTP_OK;
>
> bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
> char* Buf;
> Buf = apr_palloc(r->pool,ASE_BUFFER_SIZE);
> int size = ASE_BUFFER_SIZE;
>
> unsigned int count = 0;
> while(DataSize>0)
> {
> if((DataSize - size)<0)
> {
> size = DataSize;
> }
>
> memset(Buf,count,size);
>
> b = apr_bucket_pool_create(Buf ,size, r->pool, r->connection->bucket_alloc) ;
>
> APR_BRIGADE_INSERT_TAIL(bb, b);
> APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_flush_create(bb->bucket_alloc));
>
> if(DataSize <= size)
> {
> APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_eos_create(bb->bucket_alloc));
> ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"APR_BRIGADE_INSERT_TAIL EOS Bucket");
> }
>
> rv = ap_pass_brigade(r->output_filters, bb);
>
> if (rv != APR_SUCCESS)
> {
> ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"HTTP_INTERNAL_SERVER_ERROR ap_pass_brigade ");
> r->status = HTTP_INTERNAL_SERVER_ERROR;
> return r->status;
> }
>
> DataSize = DataSize - size;
> count++;
> ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"ap_pass_brigade, DataSize = %d and Size = %d",DataSize, size );
>
> apr_brigade_cleanup(bb);
> }
>
> ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"Out of While");
>
> apr_bucket_delete(b);
Try to remove this apr_bucket_delete from here. apr_brigade_cleanup in
the while loop deletes the buckets in the brigade. I think you delete
b twice.
Sorin
RE: cpu 100%
Posted by Niko Goutte <ng...@hotmail.com>.
> Date: Thu, 31 Mar 2011 15:01:48 +0200
> Subject: Re: cpu 100%
> From: sorinm@gmail.com
> To: modules-dev@httpd.apache.org
>
> On Thu, Mar 31, 2011 at 14:32, Niko Goutte <ng...@hotmail.com> wrote:
> >
> > Hello,
> >
> > I developped an apache module which send small data coming from file.
> > A client request from file through a Get request and data are sent with block
> > size equals to 100KB.
> > One 100KB buffer is allocated in the pool, then each buffer are used to create
> > one bucket that will be sent just after being inserted into the brigade.
> > To sum up:
> > ----------------------------------------------------------------------------------------------------------------------------
> > apr_bucket_brigade *bb;
> > apr_bucket* b;
> >
> > bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
> > Buf = apr_palloc(r->pool,100KB);
> >
> > while(lastBufferToSend==false)
> > {
> > Processing(Buf);
> >
> > b = apr_bucket_pool_create(Buf ,size, r->pool, r->connection->bucket_alloc) ;
> >
> > APR_BRIGADE_INSERT_TAIL(bb, b);
> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_flush_create(bb->bucket_alloc));
> >
> > if(lastBufferToSend)
> > {
> > APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_eos_create(bb->bucket_alloc));
> > }
> >
> > rv = ap_pass_brigade(r->output_filters, bb);
> > if (rv != APR_SUCCESS)
> > {
> > return HTTP_INTERNAL_SERVER_ERROR;
> > }
> >
> > apr_brigade_cleanup(bb);
> > }
> >
> > apr_brigade_destroy(bb);
> > ----------------------------------------------------------------------------------------------------------------------------
> >
> >
> > I want to call ap_pass_brigade for each buffer because I want the module to
> > send immediatly 100KB.
> >
> > Clients don't have to wait for the complete processing of the file more than
> > 2GB. They receive small blocks until the end.
> >
> > --------------------------------------------------------------------------------------------------------------------------
> >
> >
> > Apache Server is in prefork mode.
> > <IfModule prefork.c>
> > StartServers 8
> > MinSpareServers 5
> > MaxSpareServers 20
> > ServerLimit 256
> > MaxClients 256
> > MaxRequestsPerChild 4000
> > </IfModule>
> >
> > In worker mode, everything is excepted 10 bytes that are send in addition including value
> > "\n256\r\n" : it is very strange because the sum of every chunk corrsesponds exactly to the expected size.
> > <IfModule worker.c>
> > StartServers 2
> > MinSpareThreads 25
> > MaxSpareThreads 75
> > ThreadPerChild 64
> > MaxClients 1024
> > MaxRequestsPerChild 0
> > </IfModule>
> >
> > --------------------------------------------------------------------------------------------------------------------------
> >
> > MY PROBLEMS:
> >
> > In prefork mode, the first 8 client requests (which corresponds to the StartServers = 8) are well processed. My client received all data, everything is fine.
> > But the 9th freezes the module in ap_pass_brigade function. httpd is freezed with 100% cpu on this process.
> >
> > In worker mode, it is ok excepted the 10 bytes added. It seems that it is linked with apr_brigade_destroy or apr_bucket_delete(b).
>
>
> Are you sure that the value of lastBufferToSend changes in your while-loop?
>
> Can you post your exact code to see how you add the 10 bytes?
>
> Sorin
-------------------------------------------------------------------------------------------------------------------------------
HERE IS:
#include <httpd.h>
#include <http_config.h>
#include <http_protocol.h>
#include <http_request.h>
#include <http_log.h>
#include <ap_compat.h>
#include <apr_buckets.h>
#include <apr_strings.h>
#define ASE_FILE_SIZE 512000
#define ASE_BUFFER_SIZE 104858
module AP_MODULE_DECLARE_DATA ase_mod_module;
#define ASE_MOD_HANDLER "ase-mod.extensions"
static int ase_mod_handler(request_rec *r)
{
apr_status_t rv = APR_SUCCESS;
apr_bucket_brigade* bb = NULL;;
apr_bucket* b = NULL;;
char filename[256];
/* First, some housekeeping. */
if (((!r->handler) != 0)|| (strcmp(r->handler, ASE_MOD_HANDLER)))
{
/* r->handler wasn't "ase_mod", so it's none of our business */
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Decline processing file %s is not %s and handler %s", r->filename,ASE_MOD_HANDLER,r->handler);
return DECLINED;
}
if (r->method_number != M_GET)
{
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"Error METHOD_NOT_ALLOWED (%d)",r->method_number);
return HTTP_METHOD_NOT_ALLOWED;
}
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"%s",r->the_request);
// Construct filename
strncpy(filename, r->filename, sizeof(filename) / sizeof(char) - 1);
filename[sizeof(filename) / sizeof(char) - 1] = '\0';
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"filename = %s",filename);
int DataSize = ASE_FILE_SIZE;
ap_set_content_type(r, "video/ase");
ap_update_mtime(r, r->finfo.mtime);
ap_set_last_modified(r);
apr_table_setn(r->headers_out, "Accept-Ranges", "bytes");
r->vlist_validator = apr_pstrcat(r->pool, "X",apr_itoa(r->pool, DataSize), "\"", NULL);
ap_set_etag(r);
char content_range[64];
sprintf(content_range,"bytes %d-%d/%d",0,ASE_FILE_SIZE-1,ASE_FILE_SIZE);
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,"Add content range %s",content_range);
apr_table_setn(r->headers_out, "Content-Range",content_range);
r->status = HTTP_OK;
bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
char* Buf;
Buf = apr_palloc(r->pool,ASE_BUFFER_SIZE);
int size = ASE_BUFFER_SIZE;
unsigned int count = 0;
while(DataSize>0)
{
if((DataSize - size)<0)
{
size = DataSize;
}
memset(Buf,count,size);
b = apr_bucket_pool_create(Buf ,size, r->pool, r->connection->bucket_alloc) ;
APR_BRIGADE_INSERT_TAIL(bb, b);
APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_flush_create(bb->bucket_alloc));
if(DataSize <= size)
{
APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_eos_create(bb->bucket_alloc));
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"APR_BRIGADE_INSERT_TAIL EOS Bucket");
}
rv = ap_pass_brigade(r->output_filters, bb);
if (rv != APR_SUCCESS)
{
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,"HTTP_INTERNAL_SERVER_ERROR ap_pass_brigade ");
r->status = HTTP_INTERNAL_SERVER_ERROR;
return r->status;
}
DataSize = DataSize - size;
count++;
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"ap_pass_brigade, DataSize = %d and Size = %d",DataSize, size );
apr_brigade_cleanup(bb);
}
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,"Out of While");
apr_bucket_delete(b);
//apr_brigade_destroy(bb);
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,"End return %d",r->status);
return r->status;
}
static void ase_mod_hooks(apr_pool_t *pool)
{
if(pool){}
ap_hook_handler(ase_mod_handler, NULL, NULL, APR_HOOK_MIDDLE);
}
module AP_MODULE_DECLARE_DATA ase_mod_module = {
STANDARD20_MODULE_STUFF,
NULL, /*create dir config */
NULL, /*merge dir config */
NULL, /*create server config*/
NULL, /*merge server config */
NULL, /*command table */
ase_mod_hooks
};
-------------------------------------------------------------------------------------------------------------------------------
I would like to understand first why this module crashes with a segmentation fault in prefork mode on the 9th simple request:
curl http://IP/filename.ext
where .ext is the "ase-mod.extensions"
Thank you.
Re: cpu 100%
Posted by Sorin Manolache <so...@gmail.com>.
On Thu, Mar 31, 2011 at 14:32, Niko Goutte <ng...@hotmail.com> wrote:
>
> Hello,
>
> I developped an apache module which send small data coming from file.
> A client request from file through a Get request and data are sent with block
> size equals to 100KB.
> One 100KB buffer is allocated in the pool, then each buffer are used to create
> one bucket that will be sent just after being inserted into the brigade.
> To sum up:
> ----------------------------------------------------------------------------------------------------------------------------
> apr_bucket_brigade *bb;
> apr_bucket* b;
>
> bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
> Buf = apr_palloc(r->pool,100KB);
>
> while(lastBufferToSend==false)
> {
> Processing(Buf);
>
> b = apr_bucket_pool_create(Buf ,size, r->pool, r->connection->bucket_alloc) ;
>
> APR_BRIGADE_INSERT_TAIL(bb, b);
> APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_flush_create(bb->bucket_alloc));
>
> if(lastBufferToSend)
> {
> APR_BRIGADE_INSERT_TAIL(bb,apr_bucket_eos_create(bb->bucket_alloc));
> }
>
> rv = ap_pass_brigade(r->output_filters, bb);
> if (rv != APR_SUCCESS)
> {
> return HTTP_INTERNAL_SERVER_ERROR;
> }
>
> apr_brigade_cleanup(bb);
> }
>
> apr_brigade_destroy(bb);
> ----------------------------------------------------------------------------------------------------------------------------
>
>
> I want to call ap_pass_brigade for each buffer because I want the module to
> send immediatly 100KB.
>
> Clients don't have to wait for the complete processing of the file more than
> 2GB. They receive small blocks until the end.
>
> --------------------------------------------------------------------------------------------------------------------------
>
>
> Apache Server is in prefork mode.
> <IfModule prefork.c>
> StartServers 8
> MinSpareServers 5
> MaxSpareServers 20
> ServerLimit 256
> MaxClients 256
> MaxRequestsPerChild 4000
> </IfModule>
>
> In worker mode, everything is excepted 10 bytes that are send in addition including value
> "\n256\r\n" : it is very strange because the sum of every chunk corrsesponds exactly to the expected size.
> <IfModule worker.c>
> StartServers 2
> MinSpareThreads 25
> MaxSpareThreads 75
> ThreadPerChild 64
> MaxClients 1024
> MaxRequestsPerChild 0
> </IfModule>
>
> --------------------------------------------------------------------------------------------------------------------------
>
> MY PROBLEMS:
>
> In prefork mode, the first 8 client requests (which corresponds to the StartServers = 8) are well processed. My client received all data, everything is fine.
> But the 9th freezes the module in ap_pass_brigade function. httpd is freezed with 100% cpu on this process.
>
> In worker mode, it is ok excepted the 10 bytes added. It seems that it is linked with apr_brigade_destroy or apr_bucket_delete(b).
Are you sure that the value of lastBufferToSend changes in your while-loop?
Can you post your exact code to see how you add the 10 bytes?
Sorin