Comments for Bad CTK http://blog.charcoalphile.com On Databases, Recovery, Tech Mon, 06 Oct 2008 14:45:42 +0000 http://wordpress.org/?v=2.2.1 Comment on Python: Tips For Writing Daemons by Ben Finney http://blog.charcoalphile.com/2008/05/03/python-tips-for-writing-daemons/#comment-1013 Ben Finney Fri, 26 Sep 2008 05:41:32 +0000 http://blog.charcoalphile.com/2008/05/03/python-tips-for-writing-daemons/#comment-1013 Other problems not dealt with: * Dropping setuid and setgid privileges * PID file handling: don't start if the PID file already exists, otherwise write the PID line to the specified file, remove the PID file when program terminates * Signal handling: make sure cleanup is done in response to appropriate signals Optional extras usually present in well-behaved daemons: * Redirect stdout and stderr to syslog * Drop root privileges and switch to a specified user and group id * Operate within a chroot jail * Respawn on termination * Cooperate with operation under initd or inetd I'm rather disappointed that these widely-standardised daemon behaviours aren't present in the Python standard library. Other problems not dealt with:

* Dropping setuid and setgid privileges

* PID file handling: don’t start if the PID file already exists, otherwise write the PID line to the specified file, remove the PID file when program terminates

* Signal handling: make sure cleanup is done in response to appropriate signals

Optional extras usually present in well-behaved daemons:

* Redirect stdout and stderr to syslog

* Drop root privileges and switch to a specified user and group id

* Operate within a chroot jail

* Respawn on termination

* Cooperate with operation under initd or inetd

I’m rather disappointed that these widely-standardised daemon behaviours aren’t present in the Python standard library.

]]> Comment on My Qwest Internet Nightmare Part III by James http://blog.charcoalphile.com/2008/08/23/my-qwest-internet-nightmare-part-iii/#comment-894 James Thu, 18 Sep 2008 16:31:55 +0000 http://blog.charcoalphile.com/2008/08/23/my-qwest-internet-nightmare-part-iii/#comment-894 Hi, I found your blog on this new directory of WordPress Blogs at blackhatbootcamp.com/listofwordpressblogs. I dont know how your blog came up, must have been a typo, i duno. Anyways, I just clicked it and here I am. Your blog looks good. Have a nice day. James. Hi, I found your blog on this new directory of WordPress Blogs at blackhatbootcamp.com/listofwordpressblogs. I dont know how your blog came up, must have been a typo, i duno. Anyways, I just clicked it and here I am. Your blog looks good. Have a nice day. James.

]]> Comment on Comcast PowerBoost Is PR BS by Mason http://blog.charcoalphile.com/2008/06/16/comcast-powerboost-is-pr-bs/#comment-664 Mason Mon, 01 Sep 2008 07:00:21 +0000 http://blog.charcoalphile.com/2008/06/16/comcast-powerboost-is-pr-bs/#comment-664 I had Comcast for years , my only problem was that i had to pay for cable TV just to get internet service. So one day i decide to switch to verizon. I sign up for the FIOS service. And a few days latter a DSL modem shows up and I it is so slow I am disgusted. The DSL speed difference changed how i used the internet because it was just to slow to do most of the type of downloads i was used to. Plus my router would not work with Verizon's service and they wanted me to rent a different one from them. I went back to comcast now and I pay the extra ten bucks to get 16mbs. I love it. All is well. but then i find out Comcast is going to screw all of us with this new download limit starting Oct. 1st. I had Comcast for years , my only problem was that i had to pay for cable TV just to get internet service. So one day i decide to switch to verizon. I sign up for the FIOS service. And a few days latter a DSL modem shows up and I it is so slow I am disgusted. The DSL speed difference changed how i used the internet because it was just to slow to do most of the type of downloads i was used to. Plus my router would not work with Verizon’s service and they wanted me to rent a different one from them. I went back to comcast now and I pay the extra ten bucks to get 16mbs. I love it. All is well. but then i find out Comcast is going to screw all of us with this new download limit starting Oct. 1st.

]]> Comment on Lack Of Solutions To Deter SSH Brute Force Attacks by admin http://blog.charcoalphile.com/2008/07/17/lack-of-solutions-to-deter-ssh-brute-force-attacks/#comment-604 admin Sun, 24 Aug 2008 21:49:16 +0000 http://blog.charcoalphile.com/2008/07/17/lack-of-solutions-to-deter-ssh-brute-force-attacks/#comment-604 @Eric Cool, I'll look into it. @Eric

Cool, I’ll look into it.

]]> Comment on Lack Of Solutions To Deter SSH Brute Force Attacks by Erik Ljungstrom http://blog.charcoalphile.com/2008/07/17/lack-of-solutions-to-deter-ssh-brute-force-attacks/#comment-603 Erik Ljungstrom Sun, 24 Aug 2008 20:22:56 +0000 http://blog.charcoalphile.com/2008/07/17/lack-of-solutions-to-deter-ssh-brute-force-attacks/#comment-603 A good tool for this is http://www.ka.sara.nl/home/walter/pam_shield/ Hooks into PAM and detects failed logins and lets you define limits and what to do when they're broken etc. A good tool for this is http://www.ka.sara.nl/home/walter/pam_shield/

Hooks into PAM and detects failed logins and lets you define limits and what to do when they’re broken etc.

]]> Comment on Aggressive Caching With Memcached by Erik Ljungstrom http://blog.charcoalphile.com/2008/08/17/aggressive-caching-with-memcached/#comment-602 Erik Ljungstrom Sun, 24 Aug 2008 20:18:42 +0000 http://blog.charcoalphile.com/2008/08/17/aggressive-caching-with-memcached/#comment-602 There are far more efficient techniques for output caching than hitting memcached (as efficient as it may be). Varnish is a good bet! But I also agree with Ian, object caching is often very beneficial and works just fine in combination. There are far more efficient techniques for output caching than hitting memcached (as efficient as it may be). Varnish is a good bet! But I also agree with Ian, object caching is often very beneficial and works just fine in combination.

]]> Comment on Comcast PowerBoost Is PR BS by Cerem http://blog.charcoalphile.com/2008/06/16/comcast-powerboost-is-pr-bs/#comment-589 Cerem Sat, 23 Aug 2008 20:18:06 +0000 http://blog.charcoalphile.com/2008/06/16/comcast-powerboost-is-pr-bs/#comment-589 That would be nice except for one thing. I have comcast, and I've downloaded files over 700mb in very short order. Much shorter than that. That would be nice except for one thing.
I have comcast, and I’ve downloaded files over 700mb in very short order.
Much shorter than that.

]]> Comment on Comcast PowerBoost Is PR BS by admin http://blog.charcoalphile.com/2008/06/16/comcast-powerboost-is-pr-bs/#comment-549 admin Tue, 19 Aug 2008 02:47:26 +0000 http://blog.charcoalphile.com/2008/06/16/comcast-powerboost-is-pr-bs/#comment-549 @Expert Even so, 6mbps isn't "way" faster than 3mbps. That's like saying 56k is "way faster than 33.6k". The difference in web browsing, between 3 and 6mbps, isn't significant to the average user. Downloading large files is a different matter, however. @Expert

Even so, 6mbps isn’t “way” faster than 3mbps. That’s like saying 56k is “way faster than 33.6k”. The difference in web browsing, between 3 and 6mbps, isn’t significant to the average user. Downloading large files is a different matter, however.

]]> Comment on Comcast PowerBoost Is PR BS by Expert http://blog.charcoalphile.com/2008/06/16/comcast-powerboost-is-pr-bs/#comment-548 Expert Tue, 19 Aug 2008 02:16:09 +0000 http://blog.charcoalphile.com/2008/06/16/comcast-powerboost-is-pr-bs/#comment-548 In a lot of areas that Comcast services, Verizon is the DSL provider, and only offers up to 3mbps DSL. So even if you get 6mbps Comcast, which is the slowest, crappiest package they offer, you're still downloading twice as fast. Most of Comcast's "PR Bull" is against Verizon, not faster, modern DSL providers. In a lot of areas that Comcast services, Verizon is the DSL provider, and only offers up to 3mbps DSL. So even if you get 6mbps Comcast, which is the slowest, crappiest package they offer, you’re still downloading twice as fast. Most of Comcast’s “PR Bull” is against Verizon, not faster, modern DSL providers.

]]> Comment on Aggressive Caching With Memcached by Ian Eure http://blog.charcoalphile.com/2008/08/17/aggressive-caching-with-memcached/#comment-545 Ian Eure Sun, 17 Aug 2008 20:47:24 +0000 http://blog.charcoalphile.com/2008/08/17/aggressive-caching-with-memcached/#comment-545 As you scale up, this approach doesn't work as well. You end up needing something like a NetScaler, which handles load-balancing and caching. Depending on your traffic rates, you can enable output caching for anonymous users only and see significant benefits. You will also see improvement if you cache your data, rather than doing output caching. This shifts the load off the database, at the cost of a little more processing in your app code. You have enough flexibility that you can cache complex data and filter it down fairly easily in your application. For example, you may cache every action by all users on the site, then fetch them and only show ones for the user being viewed. You’re just a step away from explicit dirtying, which is a good goal. You just keep your data in the cache forever, and remove (or better yet, update) it when needed. With that layout, you basically never have to worry about populating it, and it’s a step towards decoupling things further, putting the DB query / cache logic into a completely different system than the cache fetch / display logic. As you scale up, this approach doesn’t work as well. You end up needing something like a NetScaler, which handles load-balancing and caching.

Depending on your traffic rates, you can enable output caching for anonymous users only and see significant benefits.

You will also see improvement if you cache your data, rather than doing output caching. This shifts the load off the database, at the cost of a little more processing in your app code. You have enough flexibility that you can cache complex data and filter it down fairly easily in your application. For example, you may cache every action by all users on the site, then fetch them and only show ones for the user being viewed.

You’re just a step away from explicit dirtying, which is a good goal. You just keep your data in the cache forever, and remove (or better yet, update) it when needed. With that layout, you basically never have to worry about populating it, and it’s a step towards decoupling things further, putting the DB query / cache logic into a completely different system than the cache fetch / display logic.

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