Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Chun Tian (binghe) wrote:
>Hi,
>
>We try to use DRBD in some reason. After some tests using tiobench
>like DRBD's performance page, we found the write rate is too low,
>almost 1/2 in Sequential Writes, 1/4 in Random Writes.
>
>We use two HP-DL140, with 2.8GHz P4 CPU*2 (with HyperThreads), 4GB
>memory and 2 SATA Maxtor hard-disk (we just use one of the two on each
>machine), and got these results:
>
>
Maybe it's nothing but I saw a decrease in performance on 2.6.15.4
using the 0.7.16 drbd module. Can't pinpoint the cause and I'am even
using this combo in production on two servers now
(planning to upgrade to vanilla 2.6.15.6 soon).
Network cards:
Ethernet controller: Intel Corporation 82546GB Gigabit Ethernet
Controller (rev 03)
Subsystem: Intel Corporation PRO/1000 MT Dual Port Server Adapter
Did you tweak the MTU size to 9000 on the nic doing the drbd work?
Cross cable or switches between the nodes?
drbd configuration details regarding performance:
net {
max-buffers 65536;
}
syncer {
rate 99M;
al-extents 521;
}
What are safe and fast settings for these .config lines?
CONFIG_DEBUG_KERNEL=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_LOG_BUF_SHIFT=17
CONFIG_DETECT_SOFTLOCKUP=y
CONFIG_DEBUG_SPINLOCK=y
CONFIG_DEBUG_SPINLOCK_SLEEP=y
CONFIG_DEBUG_HIGHMEM=y
CONFIG_DEBUG_BUGVERBOSE=y
CONFIG_DEBUG_INFO=y
CONFIG_EARLY_PRINTK=y
CONFIG_DEBUG_STACKOVERFLOW=y
CONFIG_DEBUG_STACK_USAGE=y
CONFIG_X86_FIND_SMP_CONFIG=y
CONFIG_X86_MPPARSE=y
Regards,
Leroy