On Tue, Mar 25, 2008 at 1:23 PM, Marcus Kool <marcus.kool@xxxxxxxxxxxxxxx> wrote: > I wish that the wiki for RIAD is rewritten. > Companies depend on internet access and a working Squid proxy > and therefore the advocated "no problem if a single disk fails" > is not from today's reality. > One should also consider the difference between > simple RAID and extremely advanced RAID disk systems Recently I've spent a fair bit of time benchmarking a Squid system whose COSS and AUFS storage (10GB total) + access logging are on a RAID0 array of two consumer grade SATA disks. For various reasons, I'm stuck with RAID0 for now, but I thought you might be interested to hear that the box performs pretty well. The box can handle a 600 - 700 Req/Sec Polygraph polymix-4 benchmark with a ~40% document hit ratio. usage Doubling the total storage to 20GB, increased the doc hit ratio to 55%, but hit response times began to increase noticably during the top phases. CPU was about 5% idle during the top phases. Logs were being rotated and compressed every five minutes. CPU usage never Some initial experiments suggest that removing RAID doesn't particularly improve performance, but I intend to do a more thorough set of benchmarks soon. I'm not sure how relevant this is to your discussion. I don't know how RAID0 performance is expected to compare to RAID5. I'll post here if and when I do more benchmarking without RAID. -RichardW. == Spec == CPU: Intel(R) Celeron(R) CPU 2.53GHz RAM: 3GB Disks: 2 x Seagate Barracuda 160GB Squid: 2.6.STABLE17 Linux Kernel: 2.6.23.8 FS: reiserfs == Squid Conf (extract) == # NETWORK OPTIONS http_port 800 transparent # MEMORY CACHE OPTIONS cache_mem 152 MB maximum_object_size_in_memory 50 KB # DISK CACHE OPTIONS cache_replacement_policy lru # TOTAL AVAILABLE STORAGE: 272445 MB # MEMORY STORAGE LIMIT: 46694 MB # CONFIGURED STORAGE LIMIT: 10000 MB cache_dir coss /squid_data/squid/coss0 2000 max-size=16000 cache_swap_log /squid_data/squid/%s cache_dir coss /squid_data/squid/coss1 2000 max-size=16000 cache_swap_log /squid_data/squid/%s cache_dir coss /squid_data/squid/coss2 2000 max-size=16000 cache_swap_log /squid_data/squid/%s cache_dir aufs /squid_data/squid 4000 16 256 max_open_disk_fds 0 maximum_object_size 20000 KB # LOGFILE OPTIONS debug_options ALL,1 buffered_logs on logfile_rotate 10 # MISCELLANEOUS memory_pools_limit 10 MB memory_pools off cachemgr_passwd none all client_db off
