Shared Memory ASE Internal Threads

Interfaces
File
model
Template
database
ASTC
Handler(s)
sybsystemdb
Two-phase
Commit
D
D
Separate data
and log devices
Log
Data
sybsecurity
ASE Audit
C
LRU
HK GC
tempdbs, on separate data & log
devices. On file systems with
dsync false
Log
Data
Additional
tempdbs
4K
Disk
Hot local or remote compressed
backups. Password protected. Crossplatform dump and load capability
Backup
Server
Tape
Checks and
synchronizes
licensing information
with License Server
License
Heartbeat
License
Server
User 1
User 1 thread
initiates “group
commit” and
flushes the Log
Cache
In Asynchronous
log service it
flushes the Log
Cache to disk
Log Writer *
In Asynchronous log
service, it flushes
the User Log Cache
to the Log Cache
PLC Flusher *
picks up
replicated data
Rep Agent *
* indicates
optional setup
To another ASE
Checks
periodically for
deadlocks
Deadlock
Tune
Transportable
databases
Disk mirroring.
Handles ASE
specific
mirroring
Mirror
Handler
Log
User databases are built on separate data and log
devices. Databases can share multiple devices and a
device can have fragments from multiple databases
syslogs
Data1
Data1
Performs
periodic
checkpoints
User Databases
Main ASE
checkpoint
process.
Shutdown
Checkpoint
Worker(s)
Data Cache
Overhead
ASE Static
Overhead
Spare Capacity
Standby Engine(s)
Standby Engines
Offline Engines
Mich Talebzadeh
Mich@peridale.co.uk
Version 3, Jan 2006
Free Memory
User N Log
Cache
User 1 Log
Cache
CPUs
Checkpoint
Sleep
Pending I/O
Log
LogCache
Cache
Ol
d
tra est
ns op
ac en
tio
n
Syslogshold table
(Dynamic)
C
Spinlock
Housekeeper
job. Garbage
collector,
example
deleted rows
Data
tempdb
Temporary Work
Data1
Area
Log
HK Wash
Housekeeper
job. Washes
dirty buffers.
Runs at CPU
idle time
Flushes table
and account
statistics.
Handles timeout
of detached
transactions
sybsystemprocs
device
Lock Chains
4K buffer pool *
16K buffer pool *
dbccdb Cache * Named Cache * tempdb Cache *
D
D
Wash Marker
MRU (fetch-anddiscard) strategy
C
Buffer ageing
default data cache
LRU Strategy
C
Hash Table
MRU
Partitioned
cache
Running
Task
Shared Memory
ASE
Executable
Engine N
Registers
File Descriptors/channels
Data Cache (with default 2K page example)
- Process Waiting for I/O
- Process Waiting for lock
- Process sent to sleep
Sleep Queue
Task queue cycle
1- Sleep queue
2- Runnable task queue
3- Running (on any Engine)
4- Sleep queue
Task
Network affinity
migration to the least
loaded engine
2
Running
HK Chores
sybsystemprocs
System stored
procedures
System Databases
Intra-server
cross database
two-phase
commit
ASE recommends raw devices. tempdbs can
be on file systems, tmpfs or ramdisks
master
System
Catalogue &
MDA Tables
There are as many
network handler
threads as there are
‘master' entries in
the interfaces file
Enables
Dynamically to start
and stop listeners
on any given port on
a per-engine basis
Master Device
Others
- Object
Permissions
- Column Stats
Hash Values
ASE Internal Threads
Statement
Cache
Short term memory
needs
Triggers
Cursors
Execution Plans
- Procedures
- Views
Procedure Cache
Stored procedures
Network
Handler(s)
ASE
Config
File
Runnable Task Queue
Fork
ASE
Executable
3
Operating System
Engine 1
Registers
File Descriptors/channels
1
Application Server
Initial Network
Handshake by any
engine
ASE Internal threads
can run on any engine
Fork
Running
Task
CPUs
Port
Manager
XP Server
ASE Job
Scheduler
ASE
Error log
File
ASE
Run
Server
File
ASE
Executable
Engine 0
Registers
File Descriptors/channels
Client PC
ULC, One Logical Page each
™
Total Physical Memory (read-only)
Sybase
Open Client
Maximum Memory (Dynamic)
Sybase
Open
Client
gy.
ty
strate rite of dir er
/LRU
W
ark
MRU hronous Wash M
c
e
Asyn after th
rs
buffe