HTML Question Paper focuses on “Web Performance Optimization”.
1. What is the maximum cache size for Chrome?
a) unlimited
b) 300 MB
c) 400 MB
d) 1024 MB
Answer: b
Clarification: Maximum Cache size for Chrome is 300 MB, for Safari it is unlimited, For Opera 10+ it is 400 MB, for Firefox 17 the maximum cache size is 1024 MB, for Internet Explorer 6,7,8 it is 50 MB and for Internet Explorer maximum cache size is 250 MB.
2. Which of the following is not possible compression value?
a) identity
b) deflate
c) compress
d) DNS
Answer: d
Clarification: A identity indicates no compression. Compress is a method that uses UNIX compress, it is based on LZW algorithm. Gzip is the most famous compression format, deflate is a kind of gzip without checksum header, it is little faster but less efficient. DNS stands for Domain Name System and is a naming system in computers.
3. Gzip is not fully supported by ___________
a) Netscape 4.60+
b) Firefox
c) Netscape 6+
d) IE 4+
Answer: a
Clarification: Gzip or deflate is partially supported by Netscape 4.60+. Netscape 6+, IE 4+, Opera 5+, Safari, Chrome, Lynx 2.6+ and Firefox fully support Gzip compression, IE 4.5 and 5 does not support Gzip compression, IE 5.5 and 6.0, IE 6.0 SPI, IE 6,7,8 partially support Gzip compression.
4. What is the size of PHP Module extension mysql.so?
a) 35 KB
b) 42 KB
c) 15 KB
d) 107 KB
Answer: b
Clarification: There are more than 80 extensions of the PHP source code. Mysql.so takes the size 42 KB, apc.so takes 655 KB, ffmpeg.so takes 35 KB, imap.so takes 86 KB, sasl.so takes 15 KB, tidy.so takes 42 KB, mysqli.so takes 107 KB, gd.so takes 94 KB.
5. Which of the following locking method does not supported by APC?
a) File locks
b) Spin locks
c) Dead locks
d) IPC semaphores
Answer: c
Clarification: APC supports four locking methods named File locks, Spin locks, Pthread mutex, IPC semaphores. File locks are the most stable, Spin lock gives the best performance, Pthread mutex is only available in Linux version 2.6, IPC semaphores are faster than file locks.
6. Which of the following is not the class of NoSQL?
a) Document stores
b) Multidimension stores
c) Key-value stores
d) Memcache
Answer: d
Clarification: The most basic class of NoSQL is key-value stores and commonly used in web infrastructure. Multidimension stores are more complex data relationships, here data is stored in rows and columns. MongoDB and CouchDB are the examples of Document stores.
7. Which of the following is not a kind of MySQL backup?
a) File backups
b) CSV backups
c) SQL backups
d) Table backups
Answer: d
Clarification: There are various backups in MySQL. File backups, SQL backups, backing up from a slave, CSV backups, Incremental backups are some kind of backups. File backup is the backup of MySQL database which creates a copy of files from MySQL data directory. SQL backups are alternate to File backups.
8. Which of the following is the final method to create MySQL backups?
a) LVM snapshots
b) SQL backups
c) CSV backups
d) File backups
Answer: a
Clarification: Copy of data or else database is known as backup. The final method for creating MySQL backups is LVM snapshots. It uses a copy-on-write feature of storage systems in which LVM i.e. Logical Volume Management is the most popular in Linux. It is very quick as it creates the snapshots. CSV stands for Cluster Shared Volumes backups. File backup is the backup of MySQL database which creates a copy of files from MySQL data directory. SQL backups are alternate to File backups.
9. Which of the following is not MySQL Forks?
a) MariaDB
b) OurDelta
c) Drizzle
d) Sphinx
Answer: d
Clarification: Forks are the drop-in replacement of MySQL. Some of the forks are MariaDB, Drizzle, Percona Server, OurDelta. MariaDB provides compatible general public license(GPL). Drizzle is better to fork than MariaDB, it is largely compatible with MySQL. OurDelta provides a combination of MySQL and MariaDB. Sphinx is a full text search engine of SQL.
10. Which command controls the maximum number of tables that the cache can hold?
a) table_open_cache
b) table_definition_cache
c) open_files_limit
d) read_buffer_size
Answer: a
Clarification: The option for table cache is table_open_cache. It controls the maximum number of tables that the cache can hold, we set the variable equal to the total number of table, table_definition_cache is the lightweight partner to table cache.
11. For sequential scans of tables we use ____________
a) read_buffer_size
b) join_buffer_size
c) read_rnd_buffer_size
d) sort_buffer_size
Answer: a
Clarification: For performing sequential scans of tables we used read_buffer_size, when reading sorted rows we use read_rnd_buffer_size, join_buffer_size are allocated per-session thus for multiple join buffers may be created. For performing sort operation we use sort_buffer_size.
12. How many MPMs can be loaded at a time?
a) 3
b) 1
c) 4
d) 0
Answer: b
Clarification: Multi-Process Modules i.e. MPMs is introduced by Apache 2, it controls how Apache handles the requests. We can load only one MPM at a time. But in the case of Linux, we can use two MPMs. There are two kind of MPM, worker and prefork.
13. Which version of web worker is introduced in Internet Explorer?
a) Version 3.5
b) Version 10.6
c) Version 10.0
d) Version 4.0
Answer: c
Clarification: Web workers are background threads running separate scripts. All the latest browsers support web workers. Version 3.5 of web workers is introduced in Firefox, version 10.0 in Internet Explorer, version 10.6 in Opera, version 4.0 in Chrome, version 4.0 in Safari.