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  • how to troubleshoot using rsyslog to output to a mysql database

    - by ChrisNZ
    Using FreeBSD 8.0 32 bit. I have installed rsyslogd 5.5.5 with ommysql. (installed ports /usr/ports/sysutils/rsyslog55 and /usr/ports/sysutils/rsyslog55-mysql) My rsyslog.conf file looks like: $ModLoad imudp $ModLoad imtcp $ModLoad ommysql $ModLoad immark.so $ModLoad imuxsock.so $ModLoad imklog.so $OptimizeForUniprocessor on $AllowedSender UDP, 10.0.0.0/8 $UDPServerAddress 0.0.0.0 $UDPServerRun 514 $UDPServerTimeRequery 2 # +SG560 *.* :ommysql:127.0.0.1,Syslog,sysloguser,mypassword My command line flags for rsyslogd are: -c5 -4 Checking the code with -c5 -N1 returns no errors. I have confirmed that rsyslogd is working by changing the last line to say: *.* /var/log/snapgear.log which results in messages appearing in the snapgear.log file. So it is probably something to do with my MySQL setup If I do: mysql -u sysloguser -p Syslog Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 56 Server version: 5.0.86 FreeBSD port: mysql-server-5.0.86 mysql> select * from SystemEvents; Empty set (0.00 sec) mysql> :-( I have confirmed that sysloguser has full privileges for the Syslog database. If I run rsyslogd on the console in debug mode: /usr/local/sbin/rsyslogd -f /usr/local/etc/rsyslog.conf -c5 -n -d I can see this sequence of events each time a message is received: 9244.376687256:28359280: main Q: entry added, size now log 1, phys 1 entries 9244.376705694:28359280: main Q: EnqueueMsg advised worker start 9244.376726647:28359280: Listening on UDP syslogd socket 4 (IPv4/port 514). 9244.376728602:28359280: --------imUDP calling select, active file descriptors (max 4): 4 9244.376890075:283593c0: wti 0x28306e80: worker awoke from idle processing 9244.376892031:283593c0: we deleted 0 objects and enqueued 0 objects 9244.376893986:283593c0: delete batch from store, new sizes: log 1, phys 1 9244.376895942:283593c0: msgConsumer processes msg 0/1 9244.376897898:283593c0: msg parser: flags 70, from '~NOTRESOLVED~', msg 'Jun 29 17:32:24 SG560 kernel: (20000629T1732244' 9244.376900132:283593c0: parse using parser list 0x283080e8 (the default list). 9244.376902088:283593c0: dropped LF at very end of message (DropTrailingLF is set) 9244.376904044:283593c0: Parser 'rsyslog.rfc5424' returned -2160 9244.376905999:283593c0: Message will now be parsed by the legacy syslog parser (one size fits all... ;)). 9244.376907955:283593c0: Parser 'rsyslog.rfc3164' returned 0 9244.376909910:283593c0: testing filter, f_pmask 255 9244.376911866:283593c0: Called action, logging to ommysql 9244.376918012:283593c0: actionTryResume: action state: susp, next retry (if applicable): 1277869250 [now 1277869244] 9244.376919967:283593c0: action call returned -2123 9244.376921923:283593c0: tryDoAction: unexpected error code -2123, finalizing 9244.376926113:283593c0: actionTryResume: action state: susp, next retry (if applicable): 1277869250 [now 1277869244] 9244.376928069:283593c0: ruleset: get iRet 0 from rule.ProcessMsg() 9244.376930024:283593c0: ruleset.ProcessMsg() returns 0 9244.376931980:283593c0: regular consumer finished, iret=0, szlog 0 sz phys 1 9244.376933936:283593c0: XXX: enqueueing data element 0 of 1 9244.376935891:283593c0: we deleted 1 objects and enqueued 0 objects 9244.376938126:283593c0: delete batch from store, new sizes: log 0, phys 0 9244.376940082:283593c0: regular consumer finished, iret=4, szlog 0 sz phys 0 9244.376942037:283593c0: main Q:Reg/w0: worker IDLE, waiting for work. .... I can see the Action Call to ommysql returns unexpected error code -2123 Now I am stuck! Any ideas on what to look for next? Perhaps I there are extra ports I need to install? I will be very grateful for any assistance here!

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  • Too many Bind query (cache) denied, DNS attack?

    - by Jake
    Once Bind crashed and I did: tail -f /var/log/messages I see a massive number of logs every second. Is this a DNS attack? or is there something wrong? Sometimes I see a domain in logs like this: dOmAin.com (upper and lower). As you see there is only one single domain in the logs with different IPs Oct 10 02:21:26 mail named[20831]: client 74.125.189.18#38921: query (cache) 'ns1.domain2.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 192.221.144.171#38833: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 74.125.189.17#42428: query (cache) 'ns2.domain2.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 192.221.146.27#37899: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 193.203.82.66#39263: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 8.0.16.170#59723: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 80.169.197.66#32903: query (cache) 'dOmAin.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 134.58.60.1#47558: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 192.221.146.34#47387: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 8.0.16.8#59392: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 74.125.189.19#64395: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 217.72.163.3#42190: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 83.146.21.252#22020: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 192.221.146.116#57342: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 193.203.82.66#52020: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 8.0.16.72#64317: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 80.169.197.66#31989: query (cache) 'dOmAin.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 74.125.189.18#47436: query (cache) 'ns2.domain2.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 74.125.189.16#44005: query (cache) 'ns1.domain2.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 85.132.31.10#50379: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 94.241.128.3#60106: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 85.132.31.10#59118: query (cache) 'domain.com/A/IN' denied Oct 10 02:21:26 mail named[20831]: client 212.95.135.78#27811: query (cache) 'domain.com/A/IN' denied /etc/resolv.conf ; generated by /sbin/dhclient-script nameserver 4.2.2.4 nameserver 8.8.4.4 Bind config: // generated by named-bootconf.pl options { directory "/var/named"; /* * If there is a firewall between you and nameservers you want * to talk to, you might need to uncomment the query-source * directive below. Previous versions of BIND always asked * questions using port 53, but BIND 8.1 uses an unprivileged * port by default. */ // query-source address * port 53; allow-transfer { none; }; allow-recursion { localnets; }; //listen-on-v6 { any; }; notify no; }; // // a caching only nameserver config // controls { inet 127.0.0.1 allow { localhost; } keys { rndckey; }; }; zone "." IN { type hint; file "named.ca"; }; zone "localhost" IN { type master; file "localhost.zone"; allow-update { none; }; }; zone "0.0.127.in-addr.arpa" IN { type master; file "named.local"; allow-update { none; }; };

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  • How can I recover an ext4 filesystem corrupted after a fsck?

    - by Regan
    I have an ext4 filesystem on luks over software raid5. The filesystem was operating "just fine" for several years when I was beginning to run out of space. I had a 9T volume on 6x2T drives. I began upgrading to 3T drives by doing the mdadm fail, remove, add, rebuild, repeat process until I had a larger array. I then grew the luks container, and then when I unmounted and tried to resize2fs I was given the message the filesystem was dirty and needed e2fsck. Without thinking I just did e2fsck -y /dev/mapper/candybox and it began spewing all kinds of inode being removed type messages (can't remember exactly) I killed e2fsck and tried to remount the filesystem to backup data I was concerned about. When trying to mount at this point I get: # mount /dev/mapper/candybox /candybox mount: wrong fs type, bad option, bad superblock on /dev/mapper/candybox, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so Looking back at my older logs I noticed the filesystem was giving this error each time the machine booted: kernel: [79137.275531] EXT4-fs (dm-2): warning: mounting fs with errors, running e2fsck is recommended So shame on me for not paying attention :( I then tried to mount using every backup superblock (one after another) and each attempt left this in my log: EXT4-fs (dm-2): ext4_check_descriptors: Checksum for group 0 failed (26534!=65440) EXT4-fs (dm-2): ext4_check_descriptors: Checksum for group 1 failed (38021!=36729) EXT4-fs (dm-2): ext4_check_descriptors: Checksum for group 2 failed (18336!=39845) ... EXT4-fs (dm-2): ext4_check_descriptors: Checksum for group 11911 failed (28743!=44098) BUG: soft lockup - CPU#0 stuck for 23s! [mount:2939] Attempts to restart e2fsck results in: # e2fsck /dev/mapper/candybox e2fsck 1.41.14 (22-Dec-2010) e2fsck: Group descriptors look bad... trying backup blocks... candy: recovering journal e2fsck: unable to set superblock flags on candy At this point, I decided it best to order some more drives and make an image using ddrescue Now two weeks later I have an image of the luks partition in a .img file. # ls -lh total 14T -rw-r--r-- 1 root root 14T Oct 25 01:57 candybox.img -rw-r--r-- 1 root root 271 Oct 20 14:32 candybox.logfile After numerous attempts using everything I could find online I could not coerce e2fsck to do anything on the image, so I used mkfs.ext4 -L candy candybox.img -m 0 -S and I was able to mount the dirty filesystem readonly without the journal and recover 960G of data. It gave all kinds of errors of various directories not existing and so forth but I was able to get some stuff. Which gave me some hope! I then ran e2fsck again and it had to recreate the root inode and gave a massive list of correcting group counts, I accepted the root inode creation and said no to everything else, leaving a completely empty filesystem. Re-ran again and said yes to all questions with the same result but now a "clean" but empty filesystem. extundelete gives me 0 recoverable inodes found. And now I'm stuck again, I can't come up with any other methods other than dropping to something like photorec which will give me an absolute mess with how large the filesystem was. I'm willing to re-copy the image from the original array and start over, if I can get any suggestions or ideas on a way to get more of my files back. I wish I could give more detailed logs of the commands that have run, but the output is long scrolled passed except for what gets logged to syslog and my memory is not as detailed due to the timeframe this has occurred over. Any help is greatly appreciated!

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  • KVM with one host IP and a different subnet for machines

    - by Jguy
    I've already setup a KVM host with proper IP configurations, but my host had me create DHCP and use that to assign the IP's to the machines. I want to see if there's an easier way to do it (or better). Upon my first setting out on this, I didn't find anything that pointed me in the right direction. I'm coming off a fresh install of Debian 6.0 x64, so I have nothing installed. I've logged in, queried for the below information and changed the password from my host set one. I have a Debian 6.0 x64 system with the following initial network configuration (substituted 255 in place of my real first octave): # tail /etc/network/interfaces auto eth0 iface eth0 inet static address 255.9.24.80 broadcast 255.9.24.95 netmask 255.255.255.224 gateway 255.9.24.65 # default route to access subnet up route add -net 255.9.24.64 netmask 255.255.255.224 gw 255.9.24.65 eth0 I have a /29 subnet that I want the virtual machines to use from my host: IP: 255.46.187.152 /29 Mask: 255.255.255.248 Broadcast: 255.46.187.159 Usable IP addresses: 255.46.187.153 to 255.46.187.158 I like the interface of Cloudmin, so I want to try and use that if I can to administrate my guests. So, my questions: How do I set this up on the host system the best so that I can use the additional Subnet IP's on the guests and have them accessible from the internet? I also need to host a DNS server, which means one of these VM's has to have two IP's assigned to it and accessable from the outside world. How can I do that using Cloudmin? I had a question about this here: Multiple IP addresses assigned to one KVM VM But I just reformatted the entire server and am trying to figure out a better way of doing this. Machine information: # ip route show 255.9.24.64/27 via 255.9.24.65 dev eth0 255.9.24.64/27 dev eth0 proto kernel scope link src 255.9.24.80 default via 255.9.24.65 dev eth0 brctl is empty # ip addr list 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether c8:60:00:54:b5:d8 brd ff:ff:ff:ff:ff:ff inet 255.9.24.80/27 brd 255.9.24.95 scope global eth0 inet6 fe80::ca60:ff:fe54:b5d8/64 scope link valid_lft forever preferred_lft forever Thank you for any help you can provide me. EDIT: I've installed kvm and cloudmin: aptitude install qemu-kvm libvirt-bin wget http://cloudmin.virtualmin.com/gpl/scripts/cloudmin-kvm-debian-install.sh ./cloudmin-kvm-debian-install.sh Rebooted and now my network configuration looks like this: # device: eth0 iface eth0 inet manual # default route to access subnet iface br0 inet static address 255.9.24.80 netmask 255.255.255.224 broadcast 255.9.24.95 network 255.9.24.64 bridge_ports eth0 gateway 255.9.24.65 I setup in Cloudmin the Start IP as 255.46.187.153 and End IP as 255.46.187.158. The CIDR is 29 and the gateway is 255.46.187.152. I've installed a guest with ubuntuserver 12.04 x64, which was able to get and retrieve internet resources during installation, but now cannot reach anything nor can it be reached from anything. Its network configuration is: iface eth0 inet static address 255.46.187.153 netmask 255.255.255.224 broadcast 255.46.187.159 gateway 255.46.187.152 dns-nameservers <host provided nameservers> And is not able to ping google.com through DNS or direct IP, I can't ping the VM from the outside or the host. any ideas now?

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  • Scripting Windows Shares - VBS

    - by Calvin Piche
    So i am totally new to VBS, never used it. I am trying to create multiple shares and i found a Microsoft VBS script that can do this(http://gallery.technet.microsoft.com/scriptcenter/6309d93b-fcc3-4586-b102-a71415244712) My question is, this script only allows for one domain group or user to be added for permissions where i am needing to add a couple with different permissions(got that figured out) Below is the script that i have modified for my needs but just need to add in the second group with the other permissions. If there is an easier way to do this please let me know. 'ShareSetup.vbs '========================================================================== Option Explicit Const FILE_SHARE = 0 Const MAXIMUM_CONNECTIONS = 25 Dim strComputer Dim objWMIService Dim objNewShare strComputer = "." Set objWMIService = GetObject("winmgmts:" & "{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2") Set objNewShare = objWMIService.Get("Win32_Share") Call sharesec ("C:\Published Apps\Logs01", "Logs01", "Log01", "Support") Call sharesec2 ("C:\Published Apps\Logs01", "Logs01", "Log01", "Domain Admins") Sub sharesec(Fname,shr,info,account) 'Fname = Folder path, shr = Share name, info = Share Description, account = account or group you are assigning share permissions to Dim FSO Dim Services Dim SecDescClass Dim SecDesc Dim Trustee Dim ACE Dim Share Dim InParam Dim Network Dim FolderName Dim AdminServer Dim ShareName FolderName = Fname AdminServer = "\\" & strComputer ShareName = shr Set Services = GetObject("WINMGMTS:{impersonationLevel=impersonate,(Security)}!" & AdminServer & "\ROOT\CIMV2") Set SecDescClass = Services.Get("Win32_SecurityDescriptor") Set SecDesc = SecDescClass.SpawnInstance_() 'Set Trustee = Services.Get("Win32_Trustee").SpawnInstance_ 'Trustee.Domain = Null 'Trustee.Name = "EVERYONE" 'Trustee.Properties_.Item("SID") = Array(1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0) Set Trustee = SetGroupTrustee("domain", account) 'Replace ACME with your domain name. 'To assign permissions to individual accounts use SetAccountTrustee rather than SetGroupTrustee Set ACE = Services.Get("Win32_Ace").SpawnInstance_ ACE.Properties_.Item("AccessMask") = 1179817 ACE.Properties_.Item("AceFlags") = 3 ACE.Properties_.Item("AceType") = 0 ACE.Properties_.Item("Trustee") = Trustee SecDesc.Properties_.Item("DACL") = Array(ACE) Set Share = Services.Get("Win32_Share") Set InParam = Share.Methods_("Create").InParameters.SpawnInstance_() InParam.Properties_.Item("Access") = SecDesc InParam.Properties_.Item("Description") = "Public Share" InParam.Properties_.Item("Name") = ShareName InParam.Properties_.Item("Path") = FolderName InParam.Properties_.Item("Type") = 0 Share.ExecMethod_ "Create", InParam End Sub Sub sharesec2(Fname,shr,info,account) 'Fname = Folder path, shr = Share name, info = Share Description, account = account or group you are assigning share permissions to Dim FSO Dim Services Dim SecDescClass Dim SecDesc Dim Trustee Dim ACE2 Dim Share Dim InParam Dim Network Dim FolderName Dim AdminServer Dim ShareName FolderName = Fname AdminServer = "\\" & strComputer ShareName = shr Set Services = GetObject("WINMGMTS:{impersonationLevel=impersonate,(Security)}!" & AdminServer & "\ROOT\CIMV2") Set SecDescClass = Services.Get("Win32_SecurityDescriptor") Set SecDesc = SecDescClass.SpawnInstance_() 'Set Trustee = Services.Get("Win32_Trustee").SpawnInstance_ 'Trustee.Domain = Null 'Trustee.Name = "EVERYONE" 'Trustee.Properties_.Item("SID") = Array(1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0) Set Trustee = SetGroupTrustee("domain", account) 'Replace ACME with your domain name. 'To assign permissions to individual accounts use SetAccountTrustee rather than SetGroupTrustee Set ACE2 = Services.Get("Win32_Ace").SpawnInstance_ ACE2.Properties_.Item("AccessMask") = 1179817 ACE2.Properties_.Item("AceFlags") = 3 ACE2.Properties_.Item("AceType") = 0 ACE2.Properties_.Item("Trustee") = Trustee SecDesc.Properties_.Item("DACL") = Array(ACE2) End Sub Function SetAccountTrustee(strDomain, strName) set objTrustee = getObject("Winmgmts: {impersonationlevel=impersonate}!root/cimv2:Win32_Trustee").Spawninstance_ set account = getObject("Winmgmts: {impersonationlevel=impersonate}!root/cimv2:Win32_Account.Name='" & strName & "',Domain='" & strDomain &"'") set accountSID = getObject("Winmgmts: {impersonationlevel=impersonate}!root/cimv2:Win32_SID.SID='" & account.SID &"'") objTrustee.Domain = strDomain objTrustee.Name = strName objTrustee.Properties_.item("SID") = accountSID.BinaryRepresentation set accountSID = nothing set account = nothing set SetAccountTrustee = objTrustee End Function Function SetGroupTrustee(strDomain, strName) Dim objTrustee Dim account Dim accountSID set objTrustee = getObject("Winmgmts: {impersonationlevel=impersonate}!root/cimv2:Win32_Trustee").Spawninstance_ set account = getObject("Winmgmts:{impersonationlevel=impersonate}!root/cimv2:Win32_Group.Name='" & strName & "',Domain='" & strDomain &"'") set accountSID = getObject("Winmgmts: {impersonationlevel=impersonate}!root/cimv2:Win32_SID.SID='" & account.SID &"'") objTrustee.Domain = strDomain objTrustee.Name = strName objTrustee.Properties_.item("SID") = accountSID.BinaryRepresentation set accountSID = nothing set account = nothing set SetGroupTrustee = objTrustee End Function

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  • Unable to install SQL 2008 on Windows 7

    - by Axel
    SQL 2008 install hangs on Windows 7 The story: Trying to install SQL2008 on Windows 7 hangs on SqlEngineDBStartconfigAction_install_configrc_Cpu32. What I Tried: Uninstall hangs on validation Manual uninstall using msiinv.exe and msiexec /x works Added SQL service accounts to local admins no help Turn of UAC no help Last lines in setup log: 2010-04-01 16:18:05 SQLEngine: : Checking Engine checkpoint 'GetSqlServerProcessHandle' 2010-04-01 16:18:05 SQLEngine: --SqlServerServiceSCM: Waiting for nt event 'Global\sqlserverRecComplete' to be created 2010-04-01 16:18:07 SQLEngine: --SqlServerServiceSCM: Waiting for nt event 'Global\sqlserverRecComplete' or sql process handle to be signaled 2010-04-01 16:18:07 SQLEngine: : Checking Engine checkpoint 'WaitSqlServerStartEvents' 2010-04-01 16:18:53 Slp: Sco: Attempting to initialize script 2010-04-01 16:18:53 Slp: Sco: Attempting to initialize default connection string 2010-04-01 16:18:53 Slp: Sco: Attempting to set script connection protocol to NotSpecified 2010-04-01 16:18:53 Slp: Sco: Attempting to set script connection protocol to NamedPipes 2010-04-01 16:18:53 SQLEngine: --SqlDatabaseServiceConfig: Connection String: Data Source=\.\pipe\SQLLocal\MSSQLSERVER;Initial Catalog=master;Integrated Security=True;Pooling=False;Network Library=dbnmpntw;Application Name=SqlSetup 2010-04-01 16:18:53 SQLEngine: : Checking Engine checkpoint 'ServiceConfigConnect' 2010-04-01 16:18:53 SQLEngine: --SqlDatabaseServiceConfig: Connecting to SQL.... 2010-04-01 16:18:53 Slp: Sco: Attempting to connect script 2010-04-01 16:18:53 Slp: Connection string: Data Source=\.\pipe\SQLLocal\MSSQLSERVER;Initial Catalog=master;Integrated Security=True;Pooling=False;Network Library=dbnmpntw;Application Name=SqlSetup And now comes the fun part: When I open conf mgr I can see the service running, I enabled named pipes and TCP/IP, restarted the service I'm able to connect to the server using an OLE DB connection but not with the Native Client. And what I find suspicious is the following error in my app log: .NET Runtime Optimization Service (clr_optimization_v2.0.50727_32) - Failed to compile: C:\Program Files\Microsoft SQL Server\100\Tools\Binn\VSShell\Common7\Tools\VDT\DataProjects.dll . Error code = 0x8007000b In MS connect this is reported as a bug but MS is unable to reproduce the problem altough when you search the fora I'm not the only one with this problem. So any help is appreciated.

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  • Cocoa equivalent of the Carbon method getPtrSize

    - by Michael Minerva
    I need to translate the a carbon method into cocoa into and I am having trouble finding any documentation about what the carbon method getPtrSize really does. From the code I am translating it seems that it returns the byte representation of an image but that doesn't really match up with the name. Could someone give me a good explanation of this method or link me to some documentation that describes it. The code I am translating is in a common lisp implementation called MCL that has a bridge to carbon (I am translating into CCL which is a common lisp implementation with a Cocoa bridge). Here is the MCL code (#_before a method call means that it is a carbon method): (defmethod COPY-CONTENT-INTO ((Source inflatable-icon) (Destination inflatable-icon)) ;; check for size compatibility to avoid disaster (unless (and (= (rows Source) (rows Destination)) (= (columns Source) (columns Destination)) (= (#_getPtrSize (image Source)) (#_getPtrSize (image Destination)))) (error "cannot copy content of source into destination inflatable icon: incompatible sizes")) ;; given that they are the same size only copy content (setf (is-upright Destination) (is-upright Source)) (setf (height Destination) (height Source)) (setf (dz Destination) (dz Source)) (setf (surfaces Destination) (surfaces Source)) (setf (distance Destination) (distance Source)) ;; arrays (noise-map Source) ;; accessor makes array if needed (noise-map Destination) ;; ;; accessor makes array if needed (dotimes (Row (rows Source)) (dotimes (Column (columns Source)) (setf (aref (noise-map Destination) Row Column) (aref (noise-map Source) Row Column)) (setf (aref (altitudes Destination) Row Column) (aref (altitudes Source) Row Column)))) (setf (connectors Destination) (mapcar #'copy-instance (connectors Source))) (setf (visible-alpha-threshold Destination) (visible-alpha-threshold Source)) ;; copy Image: slow byte copy (dotimes (I (#_getPtrSize (image Source))) (%put-byte (image Destination) (%get-byte (image Source) i) i)) ;; flat texture optimization: do not copy texture-id -> destination should get its own texture id from OpenGL (setf (is-flat Destination) (is-flat Source)) ;; do not compile flat textures: the display list overhead slows things down by about 2x (setf (auto-compile Destination) (not (is-flat Source))) ;; to make change visible we have to reset the compiled flag (setf (is-compiled Destination) nil))

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  • Mac gcc non-virtual thunk error

    - by fret
    I'm getting these non-virtual thunk errors only in the Deployment build of my app. It uses a private framework called Lgi. Building on 10.5.8 using XCode 3.1.4 (latest for leopard?) The error looks like this: Ld /Users/matthew/Code/Scribe-Branches/v2.00/build/Development/Scribe.app/Contents/MacOS/Scribe normal i386 cd /Users/matthew/Code/Scribe-Branches/v2.00 /Developer/usr/bin/g++-4.0 -arch i386 -L/Users/matthew/Code/Scribe-Branches/v2.00/build/Development -F/Users/matthew/Code/Scribe-Branches/v2.00/build/Development -F/Users/matthew/Code/Lgi/build -F/Users/matthew/Code/Scribe-Branches/v2.00/../../Lgi/build/Development -F/Users/matthew/Code/Scribe-Branches/v2.00/../../Lgi/build/Development -F/Users/matthew/Code/Scribe-Branches/v2.00/../../Lgi/build/Deployment -F/Users/matthew/Code/Scribe-Branches/v2.00/../../Lgi/build/Development -F/Users/matthew/Code/Scribe-Branches/v2.00/../../Lgi/build/Deployment -filelist /Users/matthew/Code/Scribe-Branches/v2.00/build/Scribe.build/Development/Scribe.build/Objects-normal/i386/Scribe.LinkFileList -framework Carbon -framework Lgi -o /Users/matthew/Code/Scribe-Branches/v2.00/build/Development/Scribe.app/Contents/MacOS/Scribe Undefined symbols: "non-virtual thunk to GWindow::OnDrop(char*, GVariant*, GdcPt2, int)", referenced from: vtable for ScribeWndin ScribeApp.o vtable for GShutdownin ScribeApp.o vtable for CalendarUiin Calendar.o vtable for CalendarViewWndin CalendarView.o vtable for CalendarConfigin CalendarView.o vtable for ScribeExportin Exp_Scribe.o vtable for GNewMailDlgin GNewMailDlg.o ....etc for lots of classes.... Anyway I know I'm not leaving those undefined because it does in fact link and run fine in the development build. Now after googling the issue the first thing to try is changing the optimization setting, which I did... and no dice. Some link error. So these virtual functions are initially defined in GDragDropTarget, and GWindow's inheritance looks like this: class LgiClass GWindow : public GView #ifndef WIN32 , public GDragDropTarget #endif (LgiClass being for __declspec export/import on win32) Any ideas on what to try next? Maybe I need to provide more info.

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  • determine parity of a bit representation of a number in MIPS

    - by Hristo
    Is there some instruction in MIPS that will determine the parity of a certain bit representation? I know to determine whether a "number" has an even parity or an odd parity is to XOR the individual bits of the binary representation together, but that seems computationally-intensive for a set of MIPS instructions... and I need to do this as quick as possible. Also, the number I'm working in is represented in Grey Code... just to throw that in there. So is there some pseudo-instruction in MIPS to determine the parity of a "number" or do I have to do it by hand? If there is no MIPS instruction, which it seems very unlikely to be, any advice on how to do it by hand? Thanks, Hristo follow-up: I found a optimization, but my implementation isn't working. unsigned int v; // 32-bit word v ^= v >> 1; v ^= v >> 2; v = (v & 0x11111111U) * 0x11111111U; return (v >> 28) & 1;

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  • NETCF - Optimized Repaint (onPaint)

    - by Nullstr1ng
    Hi Guys, I want to ask for suggestions on how to optimize a repaint in Compact Framework? GetHashCode() didn't help because it always return a different hash code. Anyway, I have a program which you can drag and resize an object in run time. This object is a transparent object and it has a PNG image which also dynamically resize relative to object client size. Though I noticed, (e.g. I have 4 transparent object and I'm dragging or resizing one) all 4 of them triggers OnPaintBackground even if the 3 are not moving. Another one when am just tapping on the one object .. it sill triggers onPaintBacground(). Anyway, I don't have a problem when this events get triggered. What I like to do is optimization and that means I only have to repaint the object when it's necessary. Can you guys please give a suggestions? here's my pseudo C# code Bitmap _backBuff; onResize() { if(_backBuff != null) _backBuff.Dispose(); _backBuff = new Bitmap(ClientSize.Width, ClientSize.Height); Invalidate(); } onPaintBackground(e) /*have to use onPaintBackground because MSDN said it's faster*/ { using(Graphics g = Graphics.FromImage(_backBuff)) { g.Clear(Color.Black); // draw background ....some interface calling here ....and paint the background // draw alpha PNG .. get hDc .. paint PNG .. release hDc } e.Graphics.DrawImage(_backBuff,0,0); } Thanks in advance.

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  • SVM Classification - minimum number of input sets for each class

    - by Amol Joshi
    Im trying to build an app to detect images which are advertisements from the webpages. Once I detect those Ill not be allowing those to be displayed on the client side. From the help that I got here in stackoverflow, I thought SVM is the best approach to my aim. So, I have coded SVM and an SMO myself. The dataset which I have got from UCI data repository has 3280 instances ( Link to Dataset- http://archive.ics.uci.edu/ml/datasets/Internet+Advertisements )where around 400 of them are from class representing Advertisement images and rest of them representing non-advertisement images. Right now Im taking the first 2800 input sets and training the SVM. But after looking at the accuracy rate I realised that most of those 2800 input sets are from non-advertisement image class. So Im getting very good accuracy for that class. So what can I do here? About how many input set shall I give to SVM to train and how many of them for each class? Thanks. Cheers. ( Basically made a new question because the context was different from my previous question. http://stackoverflow.com/questions/1991113/optimization-of-neural-network-input-data )

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  • Android ndk-build command does nothing

    - by James
    I have a similar question to that posted here: Android NDK: why ndk-build doesn't generate .so file and a new libs folder in Eclipse? ...though I am running Windows 7, not Mac os. Essentially the ndk-build command is run, gives no error but doesn't create an .so file (also, since I'm on windows this should create a .dll and not an .so?). I tried running the command from the root, jni, src folders etc. but got the same result; cmd just returns to the prompter after a few seconds. I ran it again from the jni folder with NDK_LOG=1 parameter to see what was happening. Here is a portion of the transcript of the log results after running ndk-build in the jni folder (after it successfully identified the platform, etc.)... Android NDK: Looking for jni/Android.mk in /workspace/NdkFooActivity/jni Android NDK: Looking for jni/Android.mk in /workspace/NdkFooActivity Android NDK: Found it ! Android NDK: Found project path: /workspace/NdkFooActivity Android NDK: Ouput path: /workspace/NdkFooActivity/obj Android NDK: Parsing /cygdrive/c/android-ndk-r8/build/core/default-application.mk Android NDK: Found APP_PLATFORM=android-15 in /workspace/NdkFooActivity/project.properties Android NDK: Application local targets unknown platform 'android-15' Android NDK: Switching to android-14 Android NDK: Using build script /workspace/NdkFooActivity/jni/Android.mk Android NDK: Application 'local' is not debuggable Android NDK: Selecting release optimization mode (app is not debuggable) Android NDK: Adding import directory: /cygdrive/c/android-ndk-r8/sources Android NDK: Building application 'local' for ABI 'armeabi' Android NDK: Using target toolchain 'arm-linux-androideabi-4.4.3' for 'armeabi' ABI Android NDK: Looking for imported module with tag 'cxx-stl/system' Android NDK: Probing /cygdrive/c/android-ndk-r8/sources/cxx-stl/system/Android.mk Android NDK: Found in /cygdrive/c/android-ndk-r8/sources/cxx-stl/system Android NDK: Cygwin dependency file conversion script: ...after which point it just runs the script mentioned in the last line, then terminates. Any ideas? Thanks!

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  • Axis2 webservice (aar archive) properties file

    - by XpiritO
    Hi there, guys. I'm currently developing a set of SOAP webservices over Axis2, deployed over a clustered WebLogic 10.3.2 environment. My webservices use some user settings that I want to be editable without the need for recompiling and regenerating the AAR archive. With this in mind, I chose to put them into a properties file that is loaded and consumed in runtime. Unfortunately, I'm having some questions about this: As far as I know, to achieve what I want, the only option is to put the properties file into the ../axis2/WEB-INF/classes directory of each one of the deployments (on each WebLogic instance) I currently have on my clustered configuration, and then load the file, as follows (or equivalent, this has not been verified for optimization): InputStreamReader fMainProp = new InputStreamReader(this.getClass().getResourceAsStream("myfile.properties")); Properties mainProp = new Properties(); mainProp.load(fMainProp); This is not as practical as I wanted it to be, because each time I want to alter some setting on the properties file, I have to edit each one of the files (deployed over different WebLogic instances) and there is a high probability of modifying one of these files without modifying the others. What I would like to know is if there is any (better) alternative to accomplish what I want, minimizing the potential conflict of configuration that is created by distributing and replicating the properties file through multiple WebLogic instances.

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  • How to force two process to run on the same CPU?

    - by kovan
    Context: I'm programming a software system that consists of multiple processes. It is programmed in C++ under Linux. and they communicate among them using Linux shared memory. Usually, in software development, is in the final stage when the performance optimization is made. Here I came to a big problem. The software has high performance requirements, but in machines with 4 or 8 CPU cores (usually with more than one CPU), it was only able to use 3 cores, thus wasting 25% of the CPU power in the first ones, and more than 60% in the second ones. After many research, and having discarded mutex and lock contention, I found out that the time was being wasted on shmdt/shmat calls (detach and attach to shared memory segments). After some more research, I found out that these CPUs, which usually are AMD Opteron and Intel Xeon, use a memory system called NUMA, which basically means that each processor has its fast, "local memory", and accessing memory from other CPUs is expensive. After doing some tests, the problem seems to be that the software is designed so that, basically, any process can pass shared memory segments to any other process, and to any thread in them. This seems to kill performance, as process are constantly accessing memory from other processes. Question: Now, the question is, is there any way to force pairs of processes to execute in the same CPU?. I don't mean to force them to execute always in the same processor, as I don't care in which one they are executed, altough that would do the job. Ideally, there would be a way to tell the kernel: If you schedule this process in one processor, you must also schedule this "brother" process (which is the process with which it communicates through shared memory) in that same processor, so that performance is not penalized.

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  • Optimized graph drawing for the web

    - by Andreas Petersson
    Having seen some suggestions for graphs, I wonder what's the optimum for my problem. I want to render a directed graph to a servlet/picture that is displayed in the browser. There should be some kind of optimization of position. No dependency to Swing would be preferred. Algorithms are not important, since the structure of the graph is determined by business logic. It would be desired to be able add labels to edges as well. it would be optimal if i can serve this as png/svg. Which library/service would you recommend? clarifications: 1) The question is all about Graphs - like Directed Acyclic Graph - NOT - Charts. 2) flot, Google Charts - cannot plot graphs, only charts, or have i missed something? 3) no i do not need interactivity 4) graphviz would be nice, but the grappa java library is quite outdated and is built upon swing/awt. while it may be theoretically possible to render swing to images, it would not be my favorite way to to so in a server-app. 5) it would be fine to use an online service where the images are not hosted locally. edit: added links to Wikipedia to clarify graph/chart term

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  • Worse is better. Is there an example?

    - by J.F. Sebastian
    Is there a widely-used algorithm that has time complexity worse than that of another known algorithm but it is a better choice in all practical situations (worse complexity but better otherwise)? An acceptable answer might be in a form: There are algorithms A and B that have O(N**2) and O(N) time complexity correspondingly, but B has such a big constant that it has no advantages over A for inputs less then a number of atoms in the Universe. Examples highlights from the answers: Simplex algorithm -- worst-case is exponential time -- vs. known polynomial-time algorithms for convex optimization problems. A naive median of medians algorithm -- worst-case O(N**2) vs. known O(N) algorithm. Backtracking regex engines -- worst-case exponential vs. O(N) Thompson NFA -based engines. All these examples exploit worst-case vs. average scenarios. Are there examples that do not rely on the difference between the worst case vs. average case scenario? Related: The Rise of ``Worse is Better''. (For the purpose of this question the "Worse is Better" phrase is used in a narrower (namely -- algorithmic time-complexity) sense than in the article) Python's Design Philosophy: The ABC group strived for perfection. For example, they used tree-based data structure algorithms that were proven to be optimal for asymptotically large collections (but were not so great for small collections). This example would be the answer if there were no computers capable of storing these large collections (in other words large is not large enough in this case). Coppersmith–Winograd algorithm for square matrix multiplication is a good example (it is the fastest (2008) but it is inferior to worse algorithms). Any others? From the wikipedia article: "It is not used in practice because it only provides an advantage for matrices so large that they cannot be processed by modern hardware (Robinson 2005)."

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  • Which key:value store to use with Python?

    - by Kurt
    So I'm looking at various key:value (where value is either strictly a single value or possibly an object) stores for use with Python, and have found a few promising ones. I have no specific requirement as of yet because I am in the evaluation phase. I'm looking for what's good, what's bad, what are the corner cases these things handle well or don't, etc. I'm sure some of you have already tried them out so I'd love to hear your findings/problems/etc. on the various key:value stores with Python. I'm looking primarily at: memcached - http://www.danga.com/memcached/ python clients: http://pypi.python.org/pypi/python-memcached/1.40 http://www.tummy.com/Community/software/python-memcached/ CouchDB - http://couchdb.apache.org/ python clients: http://code.google.com/p/couchdb-python/ Tokyo Tyrant - http://1978th.net/tokyotyrant/ python clients: http://code.google.com/p/pytyrant/ Lightcloud - http://opensource.plurk.com/LightCloud/ Based on Tokyo Tyrant, written in Python Redis - http://code.google.com/p/redis/ python clients: http://pypi.python.org/pypi/txredis/0.1.1 MemcacheDB - http://memcachedb.org/ So I started benchmarking (simply inserting keys and reading them) using a simple count to generate numeric keys and a value of "A short string of text": memcached: CentOS 5.3/python-2.4.3-24.el5_3.6, libevent 1.4.12-stable, memcached 1.4.2 with default settings, 1 gig memory, 14,000 inserts per second, 16,000 seconds to read. No real optimization, nice. memcachedb claims on the order of 17,000 to 23,000 inserts per second, 44,000 to 64,000 reads per second. I'm also wondering how the others stack up speed wise.

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  • How to keep unreachable code?

    - by Gabriel
    I'd like to write a function that would have some optional code to execute or not depending on user settings. The function is cpu-intensive and having ifs in it would be slow since the branch predictor is not that good. My idea is making a copy in memory of the function and replace NOPs with jumps when I don't want to execute some code. My working example goes like this: int Test() { int x = 2; for (int i=0 ; i<10 ; i++) { x *= 2; __asm {NOP}; // to skip it replace this __asm {NOP}; // by JMP 2 (after the goto) x *= 2; // Op to skip or not x *= 2; } return x; } In my test's main, I copy this function into a newly allocated executable memory and replace the NOPs by a JMP 2 so that the following x *= 2 is not executed. The problem is that I would have to change the JMP operand every time I change the code to be skipped. An alternative that would fix this problem would be: __asm {NOP}; // to skip it replace this __asm {NOP}; // by JMP 2 (after the goto) goto dont_do_it; x *= 2; // Op to skip or not dont_do_it: x *= 2; This way, as a goto uses 2 bytes of binary, I would be able to replace the NOPs by a fixed JMP of alway 2 in order to skip the goto. Unfortunately, in full optimization mode, the goto and the x*=2 are removed because they are unreachable at compilation time. Hence the need to keep that dead code.

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  • Does replace into have a where clause?

    - by Lajos Arpad
    I'm writing an application and I'm using MySQL as DBMS, we are downloading property offers and there were some performance issues. The old architecture looked like this: A property is updated. If the number of affected rows is not 1, then the update is not considered successful, elseway the update query solves our problem. If the update was not successful, and the number of affected rows is more than 1, we have duplicates and we delete all of them. After we deleted duplicates if needed if the update was not successful, an insert happens. This architecture was working well, but there were some speed issues, because properties are deleted if they were not updated for 15 days. Theoretically the main problem is deleting properties, because some properties are alive for months and the indexes are very far from each other (we are talking about 500, 000+ properties). Our host told me to use replace into instead of deleting properties and all deprecated properties should be considered as DEAD. I've done this, but problems started to occur because of syntax error and I couldn't find anywhere an example of replace into with a where clause (I'd like to replace a DEAD property with the new property instead of deleting the old property and insert a new to assure optimization). My query looked like this: replace into table_name(column1, ..., columnn) values(value1, ..., valuen) where ID = idValue Of course, I've calculated idValue and handled everything but I had a syntax error. I would like to know if I'm wrong and there is a where clause for replace into. I've found an alternative solution, which is even better than replace into (using simply an update query) because deletes are happening behind the curtains if I use replace into, but I would like to know if I'm wrong when I say that replace into doesn't have a where clause. For more reference, see this link: http://dev.mysql.com/doc/refman/5.0/en/replace.html Thank you for your answers in advance, Lajos Árpád

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  • P6 Architecture - Register renaming aside, does the limited user registers result in more ops spent

    - by mrjoltcola
    I'm studying JIT design with regard to dynamic languages VM implementation. I haven't done much Assembly since the 8086/8088 days, just a little here or there, so be nice if I'm out of sorts. As I understand it, the x86 (IA-32) architecture still has the same basic limited register set today that it always did, but the internal register count has grown tremendously, but these internal registers are not generally available and are used with register renaming to achieve parallel pipelining of code that otherwise could not be parallelizable. I understand this optimization pretty well, but my feeling is, while these optimizations help in overall throughput and for parallel algorithms, the limited register set we are still stuck with results in more register spilling overhead such that if x86 had double, or quadruple the registers available to us, there may be significantly less push/pop opcodes in a typical instruction stream? Or are there other processor optmizations that also optimize this away that I am unaware of? Basically if I've a unit of code that has 4 registers to work with for integer work, but my unit has a dozen variables, I've got potentially a push/pop for every 2 or so instructions. Any references to studies, or better yet, personal experiences?

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  • What are the primitive Forth operators?

    - by Barry Brown
    I'm interested in implementing a Forth system, just so I can get some experience building a simple VM and runtime. When starting in Forth, one typically learns about the stack and its operators (DROP, DUP, SWAP, etc.) first, so it's natural to think of these as being among the primitive operators. But they're not. Each of them can be broken down into operators that directly manipulate memory and the stack pointers. Later one learns about store (!) and fetch (@) which can be used to implement DUP, SWAP, and so forth (ha!). So what are the primitive operators? Which ones must be implemented directly in the runtime environment from which all others can be built? I'm not interested in high-performance; I want something that I (and others) can learn from. Operator optimization can come later. (Yes, I'm aware that I can start with a Turing machine and go from there. That's a bit extreme.) Edit: What I'm aiming for is akin to bootstrapping an operating system or a new compiler. What do I need do implement, at minimum, so that I can construct the rest of the system out of those primitive building blocks? I won't implement this on bare hardware; as an educational exercise, I'd write my own minimal VM.

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  • How do people know so much about programming?

    - by Luciano
    I see people in this forums with a lot of points, so I assume they know about a lot of different programming stuff. When I was young I knew about basic (commodore) and the turbo pascal (pc). Then in college I learnt about C, memory management, x86 set, loop invariants, graphs, db query optimization, oop, functional, lambda calculus, prolog, concurrency, polymorphism, newton method, simplex, backtracking, dynamic programming, heuristics, np completeness, LR, LALR, neural networks, static & dynamic typing, turing, godel, and more in between. Then in industry I started with Java several years ago and learnt about it, and its variety of frameworks, and also design patterns, architecture patterns, web development, server development, mobile development, tdd, bdd, uml, use cases, bug trackers, process management, people management if you are a tech lead, profiling, security concerns, etc. I started to forget what I learnt in college... And then there is the stuff I don't know yet, like python, .net, perl, JVM stuff like groovy or scala.. Of course Google is a must for rapid documentation access to know if a problem has been solved already and how, and to keep informed about new stuff by blogs and places like this one. It's just too much or I just have a bad memory.. how do you guys manage it?

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  • Reporting System architecture for better performance

    - by pauloya
    Hi, We have a product that runs Sql Server Express 2005 and uses mainly ASP.NET. The database has around 200 tables, with a few (4 or 5) that can grow from 300 to 5000 rows per day and keep a history of 5 years, so they can grow to have 10 million rows. We have built a reporting platform, that allows customers to build reports based on templates, fields and filters. We face performance problems almost since the beginning, we try to keep reports display under 10 seconds but some of them go up to 25 seconds (specially on those customers with long history). We keep checking indexes and trying to improve the queries but we get the feeling that there's only so much we can do. Off course the fact that the queries are generated dynamically doesn't help with the optimization. We also added a few tables that keep redundant data, but then we have the added problem of maintaining this data up to date, and also Sql Express has a limit on the size of databases. We are now facing a point where we have to decide if we want to give up real time reports, or maybe cut the history to be able to have better performance. I would like to ask what is the recommended approach for this kind of systems. Also, should we start looking for third party tools/platforms? I know OLAP can be an option but can we make it work on Sql Server Express, or at least with a license that is cheap enough to distribute to thousands of deployments? Thanks

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  • How to localize an app on Google App Engine?

    - by Petri Pennanen
    What options are there for localizing an app on Google App Engine? How do you do it using Webapp, Django, web2py or [insert framework here]. 1. Readable URLs and entity key names Readable URLs are good for usability and search engine optimization (Stack Overflow is a good example on how to do it). On Google App Engine, key based queries are recommended for performance reasons. It follows that it is good practice to use the entity key name in the URL, so that the entity can be fetched from the datastore as quickly as possible. Currently I use the function below to create key names: import re import unicodedata def urlify(unicode_string): """Translates latin1 unicode strings to url friendly ASCII. Converts accented latin1 characters to their non-accented ASCII counterparts, converts to lowercase, converts spaces to hyphens and removes all characters that are not alphanumeric ASCII. Arguments unicode_string: Unicode encoded string. Returns String consisting of alphanumeric (ASCII) characters and hyphens. """ str = unicodedata.normalize('NFKD', unicode_string).encode('ASCII', 'ignore') str = re.sub('[^\w\s-]', '', str).strip().lower() return re.sub('[-\s]+', '-', str) This works fine for English and Swedish, however it will fail for non-western scripts and remove letters from some western ones (like Norwegian and Danish with their œ and ø). Can anyone suggest a method that works with more languages? 2. Translating templates Does Django internationalization and localization work on Google App Engine? Are there any extra steps that must be performed? Is it possible to use Django i18n and l10n for Django templates while using Webapp? The Jinja2 template language provides integration with Babel. How well does this work, in your experience? What options are avilable for your chosen template language? 3. Translated datastore content When serving content from (or storing it to) the datastore: Is there a better way than getting the *accept_language* parameter from the HTTP request and matching this with a language property that you have set with each entity?

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  • Where to find algorithms for standard math functions?

    - by dsimcha
    I'm looking to submit a patch to the D programming language standard library that will allow much of std.math to be evaluated at compile time using the compile-time function evaluation facilities of the language. Compile-time function evaluation has several limitations, the most important ones being: You can't use assembly language. You can't call C code or code for which the source is otherwise unavailable. Several std.math functions violate these and compile-time versions need to be written. Where can I get information on good algorithms for computing things such as logarithms, exponents, powers, and trig functions? I prefer just high level descriptions of algorithms to actual code, for two reasons: To avoid legal ambiguity and the need to make my code look "different enough" from the source to make sure I own the copyright. I want simple, portable algorithms. I don't care about micro-optimization as long as they're at least asymptotically efficient. Edit: D's compile time function evaluation model allows floating point results computed at compile time to differ from those computed at runtime anyhow, so I don't care if my compile-time algorithms don't give exactly the same result as the runtime version as long as they aren't less accurate to a practically significant extent.

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