[squid-users] How does squid choose which cache_dir to use?
Hello I am testing FreeBSD 7.0-CURRENT and zfs. I am using: cache_dir aufs /cache0 24000 32 128 cache_dir aufs /squidcache1 9 64 256 cache_dir aufs /squidcache2 9 64 256 cache_dir aufs /squidcache3 9 64 256 Cache0= standard ufs/ffs filesystem slice of da0 /squidcache1/2/3 = a whole disk 147G (da2/da2/da3) utilizing zfs. (basicly in JBOD) (it's new, it's cool, but how does it work with squid...) Normally, (when all using ufs/ffs) all the squidcache1/2/3 dirs start filling first and the cache0 dir fills slowest. However, with the 3 using zfs, cache0 is filling much faster. Is this indicitive of the 3 cache_dirs using zfs are somehow slower, so its using cache0 more? Thanks! Nicole
Re: [squid-users] How does squid choose which cache_dir to use?
It'll choose the cache dir with the least pending disk ops, if you haven't configured any other restriction (min/max object size.) Look at the "store directory stats" page in the cache manager and see what it says. Adrian On Mon, Aug 20, 2007, Nicole wrote: > > Hello > I am testing FreeBSD 7.0-CURRENT and zfs. > > I am using: > > cache_dir aufs /cache0 24000 32 128 > cache_dir aufs /squidcache1 9 64 256 > cache_dir aufs /squidcache2 9 64 256 > cache_dir aufs /squidcache3 9 64 256 > > Cache0= standard ufs/ffs filesystem slice of da0 > /squidcache1/2/3 = a whole disk 147G (da2/da2/da3) utilizing zfs. (basicly > in JBOD) > > (it's new, it's cool, but how does it work with squid...) > > Normally, (when all using ufs/ffs) all the squidcache1/2/3 dirs start filling > first and the cache0 dir fills slowest. However, with the 3 using zfs, cache0 > is filling much faster. Is this indicitive of the 3 cache_dirs using zfs > are somehow slower, so its using cache0 more? >
Re: [squid-users] How does squid choose which cache_dir to use?
On tis, 2007-08-21 at 14:55 +0800, Adrian Chadd wrote: > It'll choose the cache dir with the least pending disk ops, if you haven't > configured any other restriction (min/max object size.) No, not with aufs. They internally all share the same queue. With aufs it currently basically selects the cache_dir based on amount of free space, or at least that's the idea.. > > Normally, (when all using ufs/ffs) all the squidcache1/2/3 dirs start > > filling > > first and the cache0 dir fills slowest. However, with the 3 using zfs, > > cache0 > > is filling much faster. Is this indicitive of the 3 cache_dirs using zfs > > are somehow slower, so its using cache0 more? Odd.. the underlying filesystem should have little or no impact on how Squid selects cache diretory. Regards Henrik
Re: [squid-users] How does squid choose which cache_dir to use?
On 21-Aug-07 My Secret NSA Wiretap Overheard Henrik Nordstrom Saying : > On tis, 2007-08-21 at 14:55 +0800, Adrian Chadd wrote: >> It'll choose the cache dir with the least pending disk ops, if you haven't >> configured any other restriction (min/max object size.) > > No, not with aufs. They internally all share the same queue. > > With aufs it currently basically selects the cache_dir based on amount > of free space, or at least that's the idea.. > >> > Normally, (when all using ufs/ffs) all the squidcache1/2/3 dirs start >> > filling >> > first and the cache0 dir fills slowest. However, with the 3 using zfs, >> > cache0 >> > is filling much faster. Is this indicitive of the 3 cache_dirs using zfs >> > are somehow slower, so its using cache0 more? > > Odd.. the underlying filesystem should have little or no impact on how > Squid selects cache diretory. > > Regards > Henrik Waah. As time goes on, it's getting even stranger. Anything I can test for or look for? /dev/da0s1h 39G4.0G 31G11%/cache0 squidcache1134G3.5G130G 3%/squidcache1 squidcache2134G 28G106G21%/squidcache2 squidcache3134G 14G120G11%/squidcache3 - Server: squid/2.6.STABLE14 Date: Thu, 23 Aug 2007 02:43:15 GMT Content-Type: text/plain Expires: Thu, 23 Aug 2007 02:43:15 GMT Last-Modified: Thu, 23 Aug 2007 02:43:15 GMT X-Cache: MISS from Via: 1.0 server:80 (squid/2.6.STABLE14) Connection: close Squid Object Cache: Version 2.6.STABLE14 Start Time: Wed, 22 Aug 2007 08:38:14 GMT Current Time: Thu, 23 Aug 2007 02:43:15 GMT Connection information for squid: Number of clients accessing cache: 2 Number of HTTP requests received: 3145661 Number of ICP messages received:1082778 Number of ICP messages sent:1089324 Number of queued ICP replies: 0 Request failure ratio: 0.00 Average HTTP requests per minute since start: 2899.2 Average ICP messages per minute since start:2001.9 Select loop called: 56871913 times, 1.145 ms avg Cache information for squid: Request Hit Ratios: 5min: 80.0%, 60min: 78.0% Byte Hit Ratios:5min: 85.6%, 60min: 84.4% Request Memory Hit Ratios: 5min: 18.4%, 60min: 18.7% Request Disk Hit Ratios:5min: 67.0%, 60min: 67.6% Storage Swap size: -824803418 KB Storage Mem size: 1024024 KB Mean Object Size: -508.60 KB Requests given to unlinkd: 0 Median Service Times (seconds) 5 min60 min: HTTP Requests (All): 0.02317 0.02317 Cache Misses: 0.03622 0.03829 Cache Hits:0.01955 0.01955 Near Hits: 0.05046 0.05046 Not-Modified Replies: 0.02069 0.02190 DNS Lookups: 0.0 0.0 ICP Queries: 0.00085 0.00080 Resource usage for squid: UP Time:65100.397 seconds CPU Time: 3659.457 seconds CPU Usage: 5.62% CPU Usage, 5 minute avg:6.65% CPU Usage, 60 minute avg: 6.54% Process Data Segment Size via sbrk(): 0 KB Maximum Resident Size: 2426132 KB Page faults with physical i/o: 0 Memory accounted for: Total accounted: 1286613 KB memPoolAlloc calls: 471286106 memPoolFree calls: 465111419 File descriptor usage for squid: Maximum number of file descriptors: 8192 Largest file desc currently in use: 44 Number of file desc currently in use: 33 Files queued for open: 0 Available number of file descriptors: 8159 Reserved number of file descriptors: 100 Store Disk files open: 2 IO loop method: kqueue Internal Data Structures: 1627350 StoreEntries 41335 StoreEntries with MemObjects 41332 Hot Object Cache Items 1621724 on-disk objects HTTP/1.0 200 OK Server: squid/2.6.STABLE14 Date: Thu, 23 Aug 2007 02:43:15 GMT Content-Type: text/plain Expires: Thu, 23 Aug 2007 02:43:15 GMT Last-Modified: Thu, 23 Aug 2007 02:43:15 GMT X-Cache: MISS from Via: 1.0 server:80 (squid/2.6.STABLE14) Connection: close Store Directory Statistics: Store Entries : 1627350 Maximum Swap Size : 301056000 KB Current Store Swap Size: -824803418 KB Current Capacity : -273% used, 374% free Store Directory #0 (aufs): /cache0 FS Block Size 2048 Bytes First level subdirectories: 32 Second level subdirectories: 128 Maximum Size: 24576000 KB Current Size: 4084006 KB Percent Used: 16.62% Current load metric: 100 / 1000 Filemap bits in use: 240838 of 1048576 (23%) Filesystem Space in use: 4201740/40393146 KB (10%) Filesystem Inodes in use: 244969/5228542 (5%) Flags: Accepted object sizes: 0 - (unlimited) bytes Removal policy: lru LRU reference age: 1.46 days Store
Re: [squid-users] How does squid choose which cache_dir to use?
On Wed, Aug 22, 2007, Nicole wrote: > > Odd.. the underlying filesystem should have little or no impact on how > > Squid selects cache diretory. > > > > Regards > > Henrik > > Waah. As time goes on, it's getting even stranger. Anything I can test for or > look for? > > /dev/da0s1h 39G4.0G 31G11%/cache0 > squidcache1134G3.5G130G 3%/squidcache1 > squidcache2134G 28G106G21%/squidcache2 > squidcache3134G 14G120G11%/squidcache3 Graph the operations per-disk. Gather data and report back. :) Adrian
Re: [squid-users] How does squid choose which cache_dir to use?
On 23-Aug-07 My Secret NSA Wiretap Overheard Adrian Chadd Saying : > On Wed, Aug 22, 2007, Nicole wrote: > >> > Odd.. the underlying filesystem should have little or no impact on how >> > Squid selects cache diretory. >> > >> > Regards >> > Henrik >> >> Waah. As time goes on, it's getting even stranger. Anything I can test for >> or >> look for? >> >> /dev/da0s1h 39G4.0G 31G11%/cache0 >> squidcache1134G3.5G130G 3%/squidcache1 >> squidcache2134G 28G106G21%/squidcache2 >> squidcache3134G 14G120G11%/squidcache3 > > Graph the operations per-disk. Gather data and report back. :) > > > Adrian Any instructions on how to do so would be very handy? :) Nicole
Re: [squid-users] How does squid choose which cache_dir to use?
On Wed, Aug 22, 2007, Nicole wrote: > Any instructions on how to do so would be very handy? :) Munin will do it. It at least graphs seperate disks out of the box under Linux. Adrian
Re: [squid-users] How does squid choose which cache_dir to use? -Oy
On 23-Aug-07 My Secret NSA Wiretap Overheard Adrian Chadd Saying : > On Wed, Aug 22, 2007, Nicole wrote: > >> > Odd.. the underlying filesystem should have little or no impact on how >> > Squid selects cache directory. >> > >> > Regards >> > Henrik >> >> Waah. As time goes on, it's getting even stranger. Anything I can test for >> or >> look for? >> >> /dev/da0s1h 39G4.0G 31G11%/cache0 >> squidcache1134G3.5G130G 3%/squidcache1 >> squidcache2134G 28G106G21%/squidcache2 >> squidcache3134G 14G120G11%/squidcache3 > > Graph the operations per-disk. Gather data and report back. :) > > > > Adrian It seems the problem may be with my test unit. I am very new to ZFS and after looking around I found that my zfs disks were reporting errors. So it is possible this is why squid was "avoiding" them. Also I have checked out munin. If anyone has a copy of some setup scripts etc that they can share, I would greatly appreciate it! Thanks! Nicole -- |\ __ /| (`\ | o_o |__ ) ) // \\ - [EMAIL PROTECTED] - Powered by FreeBSD - -- "The term "daemons" is a Judeo-Christian pejorative. Such processes will now be known as "spiritual guides" - Politicaly Correct UNIX Page
Re: [squid-users] How does squid choose which cache_dir to use? -Oy
On Thu, Aug 23, 2007, Nicole wrote: > It seems the problem may be with my test unit. I am very new to ZFS and after > looking around I found that my zfs disks were reporting errors. So it is > possible this is why squid was "avoiding" them. Ouch! > Also I have checked out munin. If anyone has a copy of some setup scripts etc > that they can share, I would greatly appreciate it! Hm, I know the ubuntu, debian and fedora munin packages come with a useful set of defaults - the only additions I made were to enable SMART disk statistics (specifically temperature and error rates.) Adrian
